Modular body cavity access system

ABSTRACT

A system for accessing a body cavity, such as a paranasal sinus, may include a sinus access member and a handle. The sinus access member may include a rigid support tube, a curved shape memory member slidably disposed at least partially within the rigid support tube, a flexible tube slidably disposed over at least part of the curved shape memory member, and proximal coupling end. The handle may include an engagement mechanism at a distal end for releasably attaching to the proximal coupling end of the sinus access member, a housing for gripping with a hand, a curving slider for extending and retracting the curved shape memory member, and an extension slider for extending and retracting the flexible tube relative to the curved shape memory member and the rigid support tube. The handle may be reusable, and the sinus access member may be disposable.

This application is being filed on 6 Jun. 2017, as a PCT Internationalpatent application, and claims priority to U.S. Provisional PatentApplication No. 62/345,891, filed Jun. 6, 2016, the disclosure of whichis hereby incorporated by reference herein in its entirety.

TECHNICAL FIELD

This disclosure is related to medical devices and methods. Morespecifically, the disclosure is related to medical devices for accessingbody cavities, such as paranasal sinuses.

BACKGROUND

Minimally invasive and less invasive surgical/medical procedures arebecoming more and more prevalent, as physicians and inventors developeffective methods and devices to treat different diseases in ways thatare less harmful to the body and require less recovery time. In many ofthese procedures, long thin endoscopes, catheters, access sheaths andthe like are used to navigate through the patient's body to theoperative site and then to perform the procedure. For example, long,flexible devices may be passed through blood vessels, nostrils, thegastrointestinal system, or the urinary tract to arrive at an operativesite. In many cases, it can be very challenging to navigate such devicesthrough sometimes very narrow, tortuous anatomical passageways, and itcan be just as challenging to visualize the navigation as well as theprocedure itself. Although great advances have been made in minimallyinvasive and less invasive surgical devices and techniques, additionalimprovements would still be desirable. Also, even some more invasivesurgical procedures might benefit from improved visualization devicesand/or access devices.

Functional endoscopic sinus surgery (FESS) is the most common type ofsurgery employed to treat chronic rhinosinusitis (CRS) and is one of thesurgical procedures discussed in this application. In a typical FESSprocedure, an endoscope is advanced into the nasal cavity along with oneor more rigid surgical instruments. The surgical instruments are used toresect soft tissue and/or bone, ablate tissue and suction blood anddebris. In most FESS procedures, the natural ostium of at least oneparanasal sinus is surgically enlarged, to improve drainage from thesinus cavity. The endoscope provides direct visualization of most of thesurgical field; however, certain anatomic structures (e.g., the uncinateprocess, ethmoidal cells, and the frontal recess) obstruct the line ofsight to hidden parts of the surgical field. Moreover, anatomicvariations (e.g., septal deviation) often further limit the access tothe area that requires treatment. Therefore, to adequately view theentire surgical field through the endoscope and safely remove diseasedor hypertrophic tissue or bone, the physician is often forced to removeor at least modify normal, healthy anatomic structures, therebyinflicting substantial collateral damage and trauma.

FESS is only one example of a procedure that would benefit from anendoscope that could more easily navigate through and around anatomicalstructures. Several other examples of minimally invasive or lessinvasive devices and methods for their use are described in U.S. Pat.Nos. 6,251,115; 5,788,713; and 7,625,356. Although many advances havebeen made, there is still a need for improved devices and methods forminimally invasive and less invasive surgical procedures.

BRIEF SUMMARY

This disclosure describes various embodiments of a device, system andmethod for accessing anatomical structures in a human or animal body,such as body cavities, one example of which is the paranasal sinuses.Generally, the embodiments include a steering mechanism coupled with anendoscope, catheter, sheath or any other suitable tool (or generallyreferred to as a “substrate”). The steering mechanism includes threecomponents a rigid member, a curved member and a flexible member. Therigid member has a default straight configuration and is the most rigidof the three components. The curved member has a default curvedconfiguration and is more rigid than the flexible member but less rigidthan the rigid member. The flexible member has a default straightconfiguration and is the least rigid of the three members. Detailsregarding these components and their function are described furtherbelow.

In one aspect of the disclosure, a system for accessing a paranasalsinus cavity of a patient includes a sinus access member coupled with ahandle. The sinus access member includes: a rigid support tube; a curvedshape memory member slidably disposed at least partially within therigid support tube, where the curved shape memory member assumes adefault curved shape when advanced out of a distal end of the rigidsupport tube; a flexible tube slidably disposed over at least part ofthe curved shape memory member, where the flexible tube assumes thedefault curved shape of the curved shape memory member when the flexibletube resides over the curved shape memory member; and a proximalcoupling end. The handle includes: an engagement mechanism at a distalend for releasably attaching to the proximal coupling end of the sinusaccess member; a housing; a curving slider coupled with the housing andreleasably coupled to a proximal end of the curved shape memory memberfor extending and retracting the curved shape memory member through thedistal end of the rigid support tube; and an extension slider coupledwith the housing and releasably coupled to a proximal end of theflexible tube for extending and retracting the flexible tube relative tothe curved shape memory member and the rigid support tube. The rigidsupport tube is fixed to the handle when the sinus access member isattached to the handle.

In some embodiments, the handle may further include a spring clutchcoupled with the curving slider and the extension slider. Optionally,the sinus access member may further include an electronics port forproviding at least one of power or data transfer to the handle. In someembodiments, the handle further includes a grip member extending from anouter surface of the housing to facilitate holding the handle. In someembodiments, the sinus access member may further include a batteryhousing, a wireless data transmitter, a fluid delivery port and/or alight source. In some embodiments, the curving slider and the extensionslider may be combined into one sliding button, such that the curvingslider is actuated when the sliding button is depressed when advanced orretracted, and the extension slider is actuated when the sliding buttonis not depressed when advanced or retracted.

The proximal coupling end of the sinus access member may couple with theengagement member of the handle in such a way that the sinus accessmember can rotate relative to the handle about a longitudinal axis drawnthrough the sinus access member and the handle. In some embodiments, thehandle may further include a rotational indexing port for detachablyreceiving and engaging a working tool, whereby the working tool issteerable and extendable by actuating the curving slider and theextension slider when the working tool is received in and engaged withthe indexing port. In some embodiments, the sinus access member mayfurther include a working tool channel configured for passage of aworking tool therethrough. For example, the working tool may include,but is not limited to, one or more cameras, optical fibers, textilethreads, metal threads, light sources, swabs, tweezers, samplecollection containers, sample collection devices, suction tubes,irrigation tubes, injection tubes, balloons, dilation tools, ultrasoundprobes, ultrasound waveguides, infrared imaging devices, probes,sensors, stylets, and/or guide wires. In some embodiments, the workingtool(s) may be included as part of the system. In some embodiments, theworking tool channel may be a lumen in the flexible tube.

In various embodiments, a radius of curvature of the curved member inthe default curved shape may be between 2 millimeters and 5 millimeters.In some embodiments, the flexible tube may be made of a shape memorymaterial. In some embodiments, the flexible tube may be disposed over atleast part of the rigid tube. In one embodiment, the flexible tube maybe a spring wrapped in polytetrafluoroethylene (PTFE) perpendicularly toa longitudinal axis of the flexible tube. Optionally, a distal head maybe coupled with a distal end of the flexible tube, and the distal headmay include a working tool. For example, the working tool may be acamera, and the system may also include wires coupled with the camerafor transferring image signals. The wires may be positioned along theinner curvature of the flexible tube when the flexible tube is curved bythe curved shape memory member. Some embodiments may further includeilluminating fibers coupled with the distal head and positioned alongthe inner curvature of the flexible tube.

In some embodiments, the curved shape memory member may include arounded distal tip and a curve immediately proximal to the roundeddistal tip. For example, the rounded distal tip may have a shape such asa bead or a ball. In some embodiments, the rigid tube may include aslanted distal tip, where a tallest point of the slanted distal tipfaces into an inner curvature of the curved shape memory member. In someembodiments, the system may further include a control unit removablycoupled with the handle and/or the sinus access member for providingpower and/or data signals to the system.

In another aspect of the present disclosure, a method for accessing atreatment area in a patient may involve: advancing a distal end of asinus access device in a straight configuration through a nostril into anasal cavity; sliding a first slider on a handle of the sinus accessdevice to advance a curved shape memory member out of a distal end of arigid tube of the sinus access device, thus allowing the curved shapememory member to assume a default curved shape outside of the rigidtube; and sliding a second slider on the handle to advance a flexibletube of the sinus access device over the curved shape memory member andto the treatment area, where the flexible tube is sufficiently flexibleto assume the default curved shape when it resides over the curved shapememory member.

In some embodiments, sliding the second slider may involve advancing theflexible tube beyond a distal end of the curved shape memory member, theflexible tube has a default straight shape, and a portion of theflexible member that extends beyond the distal end of the curved shapememory member assumes the default straight shape. In variousembodiments, the treatment area may be any suitable treatment area, suchas but not limited to a maxillary paranasal sinus, a frontal paranasalsinus, a sphenoid paranasal sinus, an ethmoid paranasal sinus, aEustachian tube and/or a skull base structure. The method may alsoinvolve: sliding the second slider to retract the flexible tube over thecurved shape memory member so that a distal end of the flexible tube isat or near a distal end of the curved shape memory member; sliding thefirst slider and the second slider to retract the curved shape memorymember into the rigid tube and the flexible tube over the rigid tube;and removing the sinus access device from the nasal cavity in thestraight configuration. In some embodiments, sliding the first slider toretract the curved shape memory member comprises retracting the curvedshape memory member until a ball-shaped distal tip at the distal end ofthe curved shape memory member contacts a slanted distal tip of therigid tube. In some embodiments, the first and second sliders arecombined into one sliding button, and the first slider is actuated bydepressing the sliding button and advancing or retracting it, and hesecond slider is actuated by not depressing the sliding button andadvancing or retracting it.

In some embodiments, the method may further involve operating a workingtool in the treatment area, where the working tool extends through aworking channel in the sinus access device, and where the working toolmay include, but is not limited to, a camera, one or more opticalfibers, one or more fiber bundles, a light source, a swab, a pair oftweezers, a suction tube, an irrigation tube, an injection tube, aballoon, a dilation tool, an ultrasound probe, an ultrasound waveguide,an infrared imaging device, a probe, a sensor, a stylet, and/or a guidewire. Optionally, the method may also include introducing fluid into thetreatment area through a fluid channel in the sinus access device and insome cases suctioning the fluid out of the treatment area through thefluid channel or a suction channel in the sinus access device. In someembodiments, the method may also involve illuminating at least one ofthe nasal cavity or the treatment area, using an illumination devicecoupled with the sinus access device, and acquiring an image of thenasal cavity and/or the treatment area, using a camera coupled with thesinus access device.

In another aspect of the present disclosure, a device for accessing aparanasal sinus cavity of a patient may include a sinus access memberand a handle. The sinus access member may include: a straight rigidsupport tube; a curved shape memory member slidably disposed at leastpartially within the rigid support tube, where the curved shape memorymember assumes a default curved shape when advanced out of a distal endof the rigid support tube; and a flexible tube slidably disposed over atleast part of the curved shape memory member and at least part of therigid tube and having a default straight shape. The flexible tube isless rigid than the curved shape memory member, and the curved shapememory member is less rigid than the rigid support tube. The handle mayinclude: a housing; a first slider coupled with the housing and aproximal end of the curved shape memory member for extending andretracting the curved shape memory member through the distal end of therigid support tube; and a second slider coupled with the housing and aproximal end of the flexible tube for extending and retracting theflexible tube relative to the curved shape memory member and the rigidsupport tube.

In some embodiments, the first and second sliders may be combined intoone sliding button. The sliding button may be pushed down/depressed toactuate the first slider and may be not pushed down/depressed to actuatethe second slider. In alternative embodiments the opposite method ofactuation is possible as well. In some embodiments, the handle mayfurther include a spring clutch coupled with the first slider and thesecond slider. Some embodiments may further include an electronics porton the sinus access member for providing at least one of power or datatransfer to the handle. The sinus access member may optionally includefurther include a battery housing, a wireless data transmitter, a fluiddelivery port and/or a light source. In some embodiments, the sinusaccess member may rotate relative to the handle about a longitudinalaxis drawn through the sinus access member and the handle.

In some embodiments, the sinus access member may also include a workingtool channel configured for passage of a working tool therethrough.Examples of working tools include, but are not limited to cameras,optical fibers, textile threads, metal threads, light sources, swabs,tweezers, sample collection containers, sample collection devices,suction tubes, irrigation tubes, injection tubes, balloons, dilationtools, ultrasound probes, ultrasound waveguides, infrared imagingdevices, probes, sensors, stylets, and guide wires. In some embodimentsthe working tool channel is a lumen in the flexible tube.

In various embodiments, a radius of curvature of the curved shape memorymember may be between 2 millimeters and 5 millimeters. In someembodiments, the flexible tube may be a spring wrapped inpolytetrafluoroethylene (PTFE) perpendicularly to a longitudinal axis ofthe flexible tube. Some embodiments may also include a distal headcoupled with a distal end of the flexible tube, where the distal headincludes a working tool. The working tool of the distal head may be, forexample, a camera, and the device may further include wires coupled withthe camera for transferring image signals, where the wires arepositioned along inner curvature of the flexible tube when the flexibletube is curved by the curved shape memory member. In some embodiments,the device may further include illuminating fibers coupled with thedistal head and positioned along the inner curvature of the flexibletube.

In some embodiments, the curved shape memory member includes a roundeddistal tip and a curve immediately proximal to the rounded distal tip.For example, the rounded distal tip may have a ball or bead shape. Therigid tube may optionally include a slanted distal tip, where a tallestpoint of the slanted distal tip faces into an inner curvature of thecurved shape memory member.

These and other aspects and embodiments are described in further detailbelow, in relation to the attached drawing figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1D are schematic illustrations of an articulating portion of anaccess device, such as a device for accessing a paranasal sinus cavityof a patient, according to one embodiment;

FIGS. 2A-2F are side views of different concentric configurations of anarticulating portion of an access device, such as a device for accessinga paranasal sinus cavity of a patient, according to various alternativeembodiments;

FIGS. 3A and 3B are side views of two different co-linear configurationsof an articulating portion of an access device, such as a device foraccessing a paranasal sinus cavity of a patient, according to twoalternative embodiments;

FIGS. 4A-4C are side perspective views of three different configurationsof an articulating portion of an access device, such as a device foraccessing a paranasal sinus cavity of a patient, according to analternative embodiment;

FIGS. 4D-4F are side perspective views of the access device of FIGS.4A-4C, in which an external sheath is removed from the image to show thedevice's internal workings;

FIG. 5 is a side view of a distal portion of an external sheath of aparanasal sinus access device, according to yet another embodiment;

FIGS. 6A and 6B are side views of distal portions of a device foraccessing a paranasal sinus cavity of a patient, according to yetanother embodiment;

FIGS. 7A and 7B are side views of a device for accessing a paranasalsinus cavity of a patient, according to yet another embodiment;

FIG. 8 is a side view of a paranasal sinus access device in positionwithin a paranasal sinus, according to yet another embodiment;

FIG. 9 is a side view of an access device, according to yet anotherembodiment;

FIG. 10 is a side view of a balloon dilation catheter, according to oneembodiment;

FIG. 11 is a side view of a balloon dilation catheter, according toanother embodiment;

FIGS. 12A-12C are side, partial cross-sectional views of an articulatingportion of an access device, according to another embodiment;

FIG. 13 is a schematic illustration of an articulating portion of anaccess device with a curved member, according to another embodiment;

FIGS. 14A-14D are perspective views of articulating portions of anarticulating device, where each embodiment has a curved member,according to four different alternative embodiments;

FIG. 15 is a side view of a split working tool, according to oneembodiment;

FIGS. 16A and 16B are perspective and front views, respectively, of adistal end of a rigid member, according to one embodiment;

FIGS. 17A-17C are perspective, front and perspective views,respectively, of a distal end of a rigid member, according to anotherembodiment;

FIGS. 18A and 18B are perspective and front views, respectively, of adistal end of a rigid member, according to another embodiment;

FIG. 19 is side, cross-sectional view of an actuation portion of anaccess device, according to one embodiment;

FIG. 20 is a perspective view of a modular cavity access system,according to one embodiment;

FIG. 21A is a perspective view of the access device portion of theaccess system of FIG. 20, including a control handle and a mechanicallysteerable worktool positioning member, according to one embodiment;

FIG. 21B is a side view of the access device of FIG. 21A, with half ofthe handle removed to show the inside of the handle;

FIG. 22A is a perspective view of the handle of the access device ofFIGS. 21A and 21B;

FIG. 22B is a perspective view of a component of the handle of FIG. 22A;

FIG. 23A is a perspective view of the steerable worktool positioningmember of FIGS. 21A and 21B, which is attachable to the handle of FIG.22A;

FIG. 23B is a perspective view of a portion the steerable worktoolpositioning member of FIG. 23A;

FIG. 23C is a perspective view of a proximal portion the steerableworktool positioning member of FIGS. 23A and 23B;

FIGS. 24A-24G are detailed perspective and elevation views of thecoupled components of the access device of FIGS. 20-23C, coupled withthe handle with housing coverings and other additional componentsremoved from both modules;

FIGS. 25A and 25B are perspective views of a portion of the accessdevice of FIGS. 20-24G, with a portion of the handle removed to showinternal components;

FIG. 26 is a perspective view of a distal portion of the support membersof the access device of FIGS. 20-25;

FIG. 27 is a perspective view of a distal portion of the support membersof the access device of FIGS. 20-26;

FIG. 28 is an exploded view of the distal support member portions of theaccess device of FIGS. 20-27;

FIG. 29 is a side view of a distal portion of a worktool positioningmember, according to one embodiment;

FIGS. 30A-30F are side views of a worktool positioning member,illustrated in a sequence showing the changing curve of a shape memoryportion as it moves from a fully extended position (FIG. 30A) to a fullyretracted position (FIG. 30F);

FIGS. 31A-31F are side views of a worktool positioning member,illustrated in a sequence showing the changing curve of a shape memoryportion as it moves from a straight configuration (FIG. 31A) to a curvedconfiguration (FIG. 31F);

FIGS. 32A-32C are perspective, side and side views, respectively, of adistal portion of a worktool including a balloon, according to twodifferent embodiments;

FIGS. 33A-33C are partial cross-sectional views of an articulatingdistal portion of an access device, according to one embodiment;

FIG. 34A-34D are partial cross-sectional views of an articulating distalportion of an access device, according to another embodiment; and

FIG. 35 is a perspective view of control handle having an ergonomicouter housing, according to one embodiment.

DETAILED DESCRIPTION

The following detailed description is organized into two main sections:(1) FIGS. 1A-19 and their corresponding description, which describegeneral principles, mechanisms and embodiments for articulating (or“steering”) any of a number of different embodiments of an accessdevice, endoscopes, catheters, working tool or the like; and (2) FIGS.20-35 and their corresponding description, which describe one embodimentof a paranasal sinus access system in detail, as well as severaloptional features and/or modification that may be made to the system,according to alternative embodiments.

In general, the embodiments described herein include an articulating orsteering mechanism, which may be incorporated into a steerableendoscope, access device, catheter, working tool or the like. Thearticulating mechanism includes three parts or components: (1) a rigidmember; (2) a curved member; and (3) a flexible member. The rigid memberand the flexible member have default configurations that are straight,and the curved member has a default configuration that is curved. Atleast two of the members are moveable longitudinally (or “translatable”)relative to one another and to the third member. In some embodiments,all three members are translatable, while in others, one of the membersis fixed. For example, in some embodiments the rigid member is fixedlyattached to a handle, and the curved member and flexible membertranslate longitudinally relative to each other and to the fixed rigidmember. Additionally, the curved member has an amount of rigidity thatis in between that of the rigid member and the flexible member. Bytranslating two or more of the members relative to one another, thecurved member can be moved from a straight shape (inside the rigidmember) to a curved shape, and in doing so, it can cause the flexiblemember to curve along with it. The combination of all three members canbe used to alter a curvature and length of an endoscope, access deviceor the like, as will be described in more detail below.

The terms “rigid member” and “flexible member” are used to describetheir relative flexibilities, compared to one another and to the curvedmember. The rigid member, in some embodiments, may be very rigid, suchas a rigid metal tube. In other embodiments, however the rigid membermay be relatively flexible, such as in a flexible catheter. In such anembodiment, the rigid member will still be more rigid than the curvedmember and the flexible member, but it may still have a degree offlexibility. Similarly, the flexible member may have a range offlexibilities, according to different embodiments. In general,therefore, these terms are used for descriptive purposes, and in anygiven embodiment the rigid member will be more rigid than the curvedmember, and the curved member will be more rigid than the flexiblemember. Aside from those specifications, the three members may have anysuitable amounts of flexibility and rigidity, including differentrigidities/flexibilities along their lengths.

In this Detailed Description, various terms are used to describe therigid member, the curved member and the flexible member. For example,the three members are often referred to as “support members” or“supporters” below. In some of the descriptions, the rigid member may becalled a “strong support member” or “strong straight support member,”the curved member may be called a “curved flexible support member” or a“curving semi-rigid support member,” and the flexible member may becalled a “flexible straight support member” or “weak straight supportmember.” Furthermore, the word “strong” may be used interchangeably withthe words “stiff,” “rigid” and “inflexible,” and “strong” may be used tomean “relatively stronger or more rigid than” one or both of the othertwo support members. The words “curved” and “curving” are used todescribe the curved support member, in that it has a default shape thatis curved, in other words having a bend or curve that is at an anglegreater than zero degrees, relative to a longitudinal axis of the curvedsupport member. Whatever terminology is used below to describe the threesupport members of the various embodiments, the terminology itselfshould not be interpreted as limiting the scope of the invention as itis defined in the claims.

Additionally, this Detailed Description focuses on one particular use ofan access system—i.e., for accessing, visualizing and/or passing toolsinto paranasal sinuses through the nasal cavities. In some embodiments,however, the devices, systems and methods described herein may be usedor modified for use in any of a number of other anatomical areas of ahuman or animal body, for any of a number of suitable procedures anduses. For example, the articulation mechanisms described herein may beused in endoscopes, catheters and other access device for cardiovascularprocedures, urological procedures and gastroenterological procedures,just to name a few. For the sake of brevity, this application will notrepeat this fact of potential additional uses each time a paranasalsinus embodiment is described. The use of the paranasal sinus example,however, should not be interpreted as limiting the scope of theinvention as it is defined in the claims. Also, the terms “sinus”,“sinus cavity” and “paranasal sinus” may be used interchangeably herein.

Exemplary embodiments described herein provide an access systemincluding a rigid member, a curved member, and a flexible member. Therigidity of the support members is graded in an escalating manner fromthe flexible member, which is the least rigid or most flexible, throughthe curved member and to the rigid member, which is the most rigid ofthe three. The curved member and/or the flexible member may be made of ashape memory material, such that it regains its original shape afterbeing temporarily deformed. The three supporters are slidably coupledwith each other, whether directly (e.g., by sliding rails, or by beingarranged in a concentric configuration), or indirectly by anothercomponent (e.g., a multilumen sheath).

In one embodiment, an operator of the access system advances the threesupporters, together, toward the sinus of a patient. At one point, therigid member stops moving forward (for example, if it is attached to ahandle, the user stops advancing the handle). The curved member and theflexible member are then advanced further, thus causing the flexiblemember and the curved member to assume a curved shape. The flexiblemember may then be advanced even further, beyond the distal end of thecurved member, and it will follow the curve but straighten out whenadvanced beyond the curved member.

Reference is now made to FIGS. 1A-1D, which are schematic illustrationsof an articulation or steering system 100, which in one embodiment maybe incorporated into a paranasal sinus access device. (In some places inthis disclosure the articulation system 100 may be referred to generallyas an “access system.”) Articulation system 100 includes a flexiblemember 102, a curved member 104 and a rigid member 106 (also referred toas “supporters 102, 104, 106”). The flexible member 102 is straightunless forced to flex, for example by encountering a rigid tissue wallor due to coupling with only unrestrained curved member 104. In theexamples set forth in FIGS. 1A-1D, each of flexible member 102, curvedmember 104 and rigid member 106 is schematically depicted as a line forexplanatory purposes. However, the supporters 102, 104, 106 can be ofany suitable shape, such as bar shaped or tube shaped. In addition, thecross-sectional shape of each of the supporters 102, 104, 106 can be anyclosed shape, such as a rectangle, a circle, an ellipse, a crescent andthe like.

Each of the three supporters 102, 104, 106 has different rigidity. Theflexible member 102 is the least rigid, the curved member 104 is thenext most rigid, and the rigid member 106 is the most rigid. Therefore,the flexible member 102 is also referred to as flexible member 102(i.e., or simply as weak supporter), and rigid member 106 is alsoreferred to as rigid member 106 (i.e., or simply as rigid member).Curved member 104 is also referred to herein as a curved member.

The three supporters 102, 104, 106 are mechanically slidably coupledwith each other. The supporters can either be coupled directly, forexample by sliding rails or by being arranged in a concentricconfiguration, or coupled via another element (e.g., by being arrangedin a co-linear configuration, or in a mix of concentric and co-linearconfiguration, enfolded within a sheath or a sleeve). An operator ofarticulation system 100 can advance each of the supporters separately oradvance all or some of the supporters together.

Flexible member 102 and/or curved member 104 may be made of a shapememory material (e.g., shape memory alloy or polymer). Thus, when eitherone of flexible member 102 or curved member 104 is forced to change fromits default shape to another shape, such as when curved member 104 isconstrained within rigid member 106 or when flexible member 102 iscaused to curve by curved member 104, it will return to its defaultshape when released from physical constraint. As mentioned above, thedefault shape of flexible member 102 is straight, and the default shapeof curved member 104 is curved.

Alternatively, flexible member 104 is made of a flexible or deflectablematerial. For example, the flexible member can be formed from a coilenfolded by a polymeric layer (e.g., PTFE film), for preventing fluidsto pass through the coil and into the access system. In this manner, theflexible member is rigid enough to push its way along the tissues of thesurrounding anatomy, and is soft enough to not damage the surroundingtissues.

Rigid member 106 is made of a material which is more rigid than that ofcurved member 104, such as a metal or metal alloy (e.g., steal), a rigidpolymer, or the like. While the rigid member 106 is more rigid than thecurved member 104 and the flexible member 102, according to someembodiments, it can be somewhat flexible or deflectable. Thereby, whenthe rigid member 106 is being pushed through the anatomy of the patient,it may be able to bend at least slightly, to facilitate passage throughthe nasal canal while minimizing damage to surrounding tissues.Alternatively, the rigid member 106 can be malleable, such that theoperator can form a bend along the rigid member 106 prior to insertioninto the patient, so that the rigid member 106 would fit the anatomy ofthe patient better. For example, a somewhat flexible, or malleable,rigid member 106 can be employed for overcoming a deviated nasal septumanatomy.

In particular, when curved member 104 overlaps a portion of (i.e., orall of) flexible member 102, curved member 104 forces the overlappedportion of flexible member 102 (e.g., the portion of flexible member 102which overlaps portion 110 of curved member 104, in FIGS. 1B-1D) toconform to the curved shape of curved member 104. However, when aportion of flexible member 102 extends beyond the length of curvedmember 104, that portion of flexible member 102 (e.g., portion 112 offlexible member 102, of FIGS. 1B-1D) regains its straight shape.

Furthermore, when rigid member 106 overlaps a portion of (i.e., or allof) curved member 104 (or vice versa), rigid member 106 forces theoverlapped portion of curved member 104 (e.g., portion 108 of curvedmember 104, in FIGS. 1B-1D) to conform to the straight shape of rigidmember 106. However, when a portion of curved member 104 is slidablyextended beyond the length of rigid member 106, that portion of curvedmember 104 (e.g., portion 110 of curved member 104,of FIGS. 1B-1D)regains its curved shape (also imposing curvature on flexible member inthat overlap region).

As shown in FIG. 1A, rigid member 106 and curved member 104 are fullyoverlapping, and therefore rigid member 106 forces curved member 104 toconform to a straight shape. As can be seen in FIGS. 1B-1D, the curveangle of the path of articulation system 100 is determined by the radiusof curvature of curved member 104, and by the length of portion 110 ofcurved member 104, which does not overlap rigid member 106.

The curve angle (i.e., also referred to as the curvature angle) ofarticulation system 100 is defined by the angle between rigid member 106(i.e., or the portion of flexible member 102, which is parallel thereto)and portion 112 of flexible member 102. The radius of curvature ofcurved member 104 can be defined as the radius of an imaginary circulararc that best approximates the curve of curved member 104. Thus, theradius of curvature is a structural property of curved member 104.

Put another way, the radius of curvature of the access system is ameasure of the acuteness of the bending of the access system. Inparticular, a small value of radius of curvature (e.g., about 2 mm) ofthe access system relates to an acute bend, and a larger radius ofcurvature value (e.g., about 5 mm) relates to a less acute bend. Thecurvature of the access system does not necessarily fit a circular arc,and can fit a circular, elliptical or other non-linear arc. Thus,different sections of the curved member can have different radii ofcurvatures.

The radius of curvature of curved member 104, and therefore ofarticulation system 100, is predetermined and constant. On the otherhand, the curve angle of articulation system 100 is determined by thelength of curved member that does not overlap rigid member 106. Thelength of portion 110 of curved member 104, which does not overlap rigidmember 106, is controlled by the operator of articulation system 100(i.e., who can either push curved member 104 distally with respect torigid member 106, or pull rigid member 106 proximally). For example, thecurve angle of articulation system 100 is increased with the increase inthe length of non-overlapping portion 110 from the length depicted inFIG. 1B, to the length depicted in FIG. 1C, and further to the length indepicted in FIG. 1D. In summary, the curve angle of articulation system100 is a function of the predetermined radius of curvature of curvedmember104, and of the length of portion 110 of curved member 104, ascontrolled by the operator. Thus, the curve angle can be dynamicallydetermined to fit the anatomy of a specific patient.

In this manner, the operator of articulation system 100 controls thecurve angle of articulation system 100 by controlling the length ofportion 110 of curved member 104, which extends beyond rigid member 106.During insertion of articulation system 100 into the paranasal sinus ofthe patient, the operator of the access system pushes all supporterstogether distally (i.e., in the examples set forth in FIGS. 1A-1D, thedistal direction is toward the left hand side of the figure) untilreaching a first point, in which a curved movement is required foraccessing the sinus. The operator pushes distally both curved member 104and flexible member 102 (i.e., while holding rigid member 106 in place)until reaching the desired curve angle. Alternatively, the operatorfirst pushes curved member 104 distally until reaching the desired curveangle, and then pushes flexible member 102. Finally, the operator pushesdistally only flexible member 102 (i.e., while holding both rigid member106 and curved member 104 in place) until accessing the sinus or untilreaching the required location within the sinus.

As the curved member conforms to the straight shape of the rigid memberwhen both are overlapping, the access system exhibits substantially nobulges or protrusions during insertion into the nasal cavity. Only whenthe access system is positioned in the desired location near theparanasal sinuses, the curved member is extended from the rigid memberand the access system forms a bending path. Thus, the damage to thetissues surrounding the access system on the way to the sinus cavity isreduced as the access system maintains a small cross section with noprotrusions or bulges (unless desired as will be described furtherherein below).

In accordance with another embodiment, an access system includes severalcurved members each having a different radius of curvature. For example,an access system kit includes several access systems, each having curvedmember of different curvature, such that the operator can choose theaccess system curvature which best fits the anatomy of the patient.Alternatively, the access system kit includes several curved membersthat can be coupled with the other supporters of the access system(i.e., the strong and the flexible members). Additionally, the operatorcan couple several curved members for forming together a singlecontinuous curved member having several sections of differentcurvatures. Thereby, the operator can determine the radius of curvatureof the curved member, and thus the radius of curvature of the accesssystem. Thereby, the operator can adjust the radius of curvature of theaccess system to the anatomy of the patient.

In accordance with a further embodiment, the radius of curvature of thecurved member can vary along the length of the curved member. Forexample, the radius of curvature can be very small at the distal end ofthe curved member such that even when a short section thereof extendsbeyond the rigid member, the curvature angle of the access system islarge. That is, the first few millimeters from the distal end of thecurved member have a very small radius of curvature, while the rest ofthe curved member has a longer radius of curvature.

Referring now to FIGS. 2A-2F, side views of a distal, articulatingportion of several alternative embodiments of an access device 150 areprovided. As with the previous embodiment, access device 150 may beconfigured for use in accessing a paranasal sinus cavity of a patient.Access device 150 includes three concentric tubes: an external tube, amiddle tube, and an internal tube. The three tubes have differentcharacteristics in terms of their rigidity and shape memory (i.e.,similar to the supporters 102, 104, 106 of FIGS. 1A-1D). In particular,one of the tubes serves as a straight semi-rigid tube (i.e., flexibletube or weak straight tube), another tube serves as a curved semi-rigidtube (i.e., curved tube), and the third tube serves as a straight rigidtube (i.e., rigid tube or strong straight tube).

In all of the configurations presented in FIGS. 2A-2F, a tube 152 isstraight and is semi-rigid (i.e., similarly to flexible member 102 ofFIGS. 1A-1D). That is, tube 152 is straight and regains its straightshape when not constrained. The rigidity of tube 152 is the lowest ofthe three tubes. A tube 154 is curved and is semi-rigid (i.e., similarlyto curved member 104 of FIGS. 1A-1D). Tube 154 is curved and regains itscurved shape when not constrained. The rigidity of tube 154 is higherthan that of weak straight tube 152. A tube 156 is straight and is rigid(i.e., similarly to rigid member 106 of FIGS. 1A-1D). The rigidity oftube 156 is the highest of the three tubes.

With reference to FIG. 2A, access device 150 includes a weak straightexternal tube 152, a curved middle tube 154, and a strong straightinternal tube 156. Internal tube 156 slidably passes via middle tube154, which in turn slidably passes via external tube 152. In the exampleset forth in FIGS. 2A-2F the distal direction is toward the left handside of the Figure.

Access device 150 provides a route (i.e., a work channel) through whichat least one tool (not shown) can reach areas within the paranasal sinusof a patient. In other words, the work channel is defined as a passagewithin access device 150 for enabling a work tool to access to the sinuscavity. The work channel can be a dedicated passage, such as a dedicatedlumen within a multilumen sheath enfolding access device 150. The workchannel can be incorporated into one of the supporters. For example, thelumen of rigid member 156 of FIG. 2A is defined as the work channel ofaccess device 150. Alternatively, the work channel can be defined as thelumen within the flexible member. Once the access system accesses thesinus cavity, the strong and the curved members of the access system areretracted, and the lumen of the remaining flexible member functions asthe work channel. The work channel can be embodied as an external sleeveor sheath enfolding the access system. Once the access system enters thesinus cavity, the supporters of the access system are retracted, and theremaining enfolding sheath functions as the work channel. The workchannel can be embodied as the intra-volume between the external sheathand the supporters, or the outer most supporter.

The tube shaped supporters of FIGS. 2A-2F are merely examples, and aswould be detailed further herein below, the supporters can assume anyelongated shape, whether tubular or non-tubular, and have anycross-section (e.g., circular, oval, rectangular, hexagonal and thelike). Thus, for example, the work channel can pass via any supporterhaving a lumen running therein regardless of the cross-section of thesupporter. Similarly, every feature of the invention that is describedherein with reference to tubular supporters, can also be employed incase of other supporters as well.

The work tool is employed for performing an action within the accessedparanasal sinus. The at least one tool can be for example, a camera, oneor more optical fibers, one or more optical bundles, a swab forcollecting tissue samples, a suction tube for draining the accessedparanasal sinus, an irrigation tube or an injecting tube for injectingfluids for cleaning the sinus (e.g., saline water) or for injectingother fluids into the sinus (e.g., localized drug delivery), a surgerytool for performing surgical operation in the sinus, a balloon fordilating the ostium of a sinus or opening a sinus blockage, a diagnostictool such as an ultrasound or an infrared imaging device, a probe, asensor, a stylet, a guide wire, and the like. Alternatively, the tool(e.g., a swab) is coupled with external tube 152. Further alternatively,the joint lumen of 152, 154 and 156 constitutes a tube through whichfluids can be passed into the sinus, obviating the need for a dedicatedtube to be inserted therethrough.

The access system thus provides access into the sinus cavity for atleast one working tool via the work channel. By enabling all requiredtools to access the sinus cavity through a single access system, theoperator can operate the access system and the working tools with only asingle hand (i.e., single handed operation). For example, instead ofmaneuvering a first device (e.g., a camera endoscope) into the sinuscavity with a first hand, and maneuvering a second separate device(e.g., a tissue sampling tool) into the sinus cavity with the otherhand, the operator of the access system of the invention, guides theaccess system into the sinus cavity single handedly, and once within canoperate a tissue sampling tool while viewing the images acquired by acamera fixed to the distal end of the access system.

The route of access device 150 includes a turn or a curve in order tobypass physical or anatomical obstacles (e.g., due to anatomy of thenasal cavity and paranasal sinuses). The position of the curve along theroute of access device 150 and the angle of the curve (i.e., curveangle) are controlled by the shape-memory designed into the system andby the operator of access device 150 (as will be related furtherhereinbelow with reference to FIGS. 20 et seq., a modular systemprovides a way for sinus access members 908 having different shapememory profiles to be used with the same handle 900). As mentioned abovewith reference to FIGS. 1B-1D, the angle of the curve (i.e., alsoreferred to as a bend) is determined by the relative positions of strongstraight tube 156 and curved semi-rigid tube 154, and by the radius ofcurvature of curved semi-rigid tube 154. In particular, the further thatcurved tube 154 extends beyond strong straight tube 156, the larger theangle of the curve. Once the operator of access device 150 sets theangle of the curve, the operator pushes weak straight tube 152 furtherdistally in the set direction towards a selected area within theparanasal sinus of the patient. The operator can than push the tool viathe work channel created by the lumens inside tubes 152, 154 and 156towards the selected area.

In the configuration of FIG. 2B, external tube 154 is the curvedsemi-rigid tube, middle tube 152 is the weak straight tube, and internaltube 156 is the strong straight tube. In the configuration of FIG. 2C,external tube 154 is the curved semi-rigid tube, middle tube 156 is thestrong straight tube, and internal tube 152 is the weak straight tube.In the configuration of FIG. 2D, external tube 156 is the strongstraight tube, middle tube 154 is the curved tube, and internal tube 152is the weak straight tube. In the configuration of FIG. 2E, externaltube 152 is the weak straight tube, middle tube 156 is the strongstraight tube, and internal tube 154 is the curved tube. In theconfiguration of FIG. 2F, external tube 156 is the strong straight tube,middle tube 152 is the weak straight tube, and internal tube 154 is thecurved tube.

Referring now to FIGS. 3A and 3B, two alternative embodiments of adistal portion of an access device 200 are illustrated. Access system200 (which again may be used for accessing paranasal sinuses) mayinclude an external sheath 208, a flexible member 202, a curved member204, and a rigid member 206. The three supporters 202, 204, 206 passslidably within external sheath 208 alongside each other (i.e., thesupporters are co-linear). External sheath 208 mechanically couplessupporters 202, 204 and 206. For example, external sheath 208 couplescurved member 204 to rigid member 106, such that when they overlap,curved member 104 conforms to the straight shape of rigid member 106.

As in previous embodiments, the path (i.e., route) followed by accesssystem 200 during insertion into the paranasal sinus includes a curve(i.e., a bend), which position and angle are controllable by an operatorof access system 200. In a similar manner to articulation system 100 ofFIGS. 1A-1D, the curve angle is set by the distance by which the distalend of curved member 204 extends beyond the distal end of rigid member206.

External sheath 208 enfolds supporters 202, 204 and 206, and is made ofa sealed material. Thereby, sheath 208 prevents contact between thesupporters and the tissues of the patient. It is therefore not necessaryto disinfect or to sterilize the supporters (and other tools andcomponents which may reside within external sheath 208), for example,when being used among different patients. External sheath 208, whichcomes into direct contact with the tissues of the patient (e.g., nasalcavity and paranasal sinus) during use, is disposable. That is, externalsheath 208 is a single use disposable element designed to enable theother components of access system 200 to be re-used for another patientby simply replacing external sheath 208. Alternatively, external sheath208 is made from an easily disinfected or sterilizable material, and canbe disinfected or sterilized when being used among different patients.Further alternatively, an additional single use elastic sheath mayenfold 208. In addition, external sheath 208 is formed of a flexiblematerial. Thereby, sheath 208 when extended distally beyond flexiblemember 202 functions as an atraumatic tip for gentle probing ofsensitive anatomies.

Each of flexible member 202, curved member 204, and rigid member 206 canbe bar shaped or tube shaped. The cross section of each of thesupporters can be any closed shape, such as a circle, a rectangle, anellipse and the like. In the case where two supporters or more areconstructed as tubes they can be either concentric or run in parallel toeach other.

With reference to FIG. 3A, flexible member 202, curved member 204 andrigid member 206 are colinear and are sliding along each other. Withreference to FIG. 3B, flexible member 202 and rigid member 206 are tubeshaped. flexible member 202 slides within rigid member 206 (i.e.,flexible member 202 and rigid member 206 are concentric). curved member204 is co-linear to flexible member 202 and rigid member 206 and slidesalongside both. Alternatively, any couple of the supporters can be tubeshaped and concentric while the third slides alongside both.

In accordance with another embodiment, external sheath 208 can replaceflexible member 202 (i.e., such that flexible member 202 is omitted fromthe access system). Thereby, external sheath functions as both theflexible member and the external sheath isolating the access system fromthe surrounding tissues. The work channel of access system 200 can bedefined as a lumen or a passage within external sheath 208.

Reference is now made to FIGS. 4A-4F. FIGS. 4A-4C are schematicillustrations of a system, generally referenced 250, for accessing aparanasal sinus of a patient, according to another embodiment. FIGS.4D-4F are schematic illustrations of the access system of FIGS. 4A-4C,in which the external sheath is removed from the image such that theinternal portions of the access system are exposed to the viewer forbetter clarifying the operation thereof.

Access system 250 includes an external sheath 258, a flexible member252, a curved member 254, and a rigid member 256. Each of flexiblemember 252, curved member 254 and rigid member 256 is similar in termsof rigidity and shape memory properties to each of flexible member 102,curved member 104 and rigid member 106 of FIGS. 1A-1D, respectively.Flexible member 252 is tube-shaped, and curved member 254 and rigidmember 256 are both bar shaped. The supporters are co-linear.

Typical dimensions of an entry to a healthy sinus cavity are about 2 mm.Therefore, the maximal outer diameter of access system 250 is about 2.5mm, and preferably a bit less, for example, 2.2 mm-2.4 mm for mitigatingor preventing damage, pain, and inconvenience to the patient. However,it should also be noted, again, that dilation of the tissues beingpassed through may be desirable in certain circumstances.

With reference to FIG. 4A, another embodiment of an access system 250 isdepicted in an initial configuration thereof, in which both rigid member256 and curved member 254 are fully overlapping. In the initialconfiguration, rigid member 256 forces curved member 254 to conform tothe straight shape of rigid member 256. The dotted lines in FIG. 4Aindicate the distal tip of supporters 252, 254, and 256. Alternatively,the distal tip of each or some of the supporters is positionedproximally to the distal tip of sheath 258. Further alternatively, thedistal tip of sheath 258 is occupied by a functional distal head, asdetailed further herein below with reference to FIG. 5.

With reference to FIG. 4D, access system 250 is depicted with externalsheath 258 being removed from the image, for exposing supporters 252,254, and 256 to the viewer. As mentioned herein above with reference toFIG. 4A, and as can be seen in FIG. 4D, both curved member 254 andflexible member 252, when overlapping rigid member 256, conform to thestraight shape of rigid member 256.

With reference to FIGS. 4B and 4E, an operator of access system 250pushes curved member 254 and flexible member 252 in the distal direction(i.e., in the example set forth in FIGS. 4A-4F the distal direction istoward the left hand side of the Figure). Thereby, the overlap betweenrigid member 256 and curved member 254 becomes smaller, or even vanishes(i.e., depending on the distance by which curved member 254 and flexiblemember 252 are pushed by the operator). A portion of curved member 254which is not overlapping rigid member 256 regains its curved shape andforces a corresponding portion of flexible member 252, to conform to thecurved shape of curved member 254. Alternatively, the operator pullsrigid member 256 proximally for achieving the same effect and exposingat least a portion of curved member 254 from overlapping rigid member256.

Shape memory materials can regain their original shape after beingconstrained to a different shape. However, the shape memory is notunlimited, and an element made of shape memory material which is highlydeformed, may not fully regain its original shape. Curved member 254 isstraightened by rigid member 256 when they are overlapping each other,and is thereby deformed from its original curved shape. For minimizingthe deformation of curved member 254, curved member 254 is positionedfurthest away from the direction of curve of access system 250 (i.e., atthe extrados of the curved path of access system). As can be seen inFIGS. 4B and 4E, curved member 254 is positioned off-center withinsheath 258. In particular, curved member 254 is positioned furthest awayfrom the direction of curve of sheath 258 (i.e., and access system 250),thereby its radius of curvature is bigger than if it would have beenconcentric with sheath 258. Thus, by positioning curved member 254off-center and away from the curve direction, the radius of curvature ofcurved member 254 is increased, for the same radius of curvature ofsheath 258. The larger the radius of curvature of curved member 254 theless it is being deformed when straightened by rigid member 256.

With reference to FIGS. 4C and 4F, the operator of access system 250further pushes flexible member 252 distally of both rigid member 256 andcurved member 254. Thereby, flexible member 252 regains its straightshape. In the final configuration of access system 250, as depicted inFIGS. 4C and 4F, a proximal section of external sheath 258 (i.e., andaccordingly of access system 250) is substantially in a straight shape.A middle section of external sheath 258, which is occupied by a portionof curved member 254 that is not overlapping rigid member 256, is in acurved shape. The section of external sheath 258 which is occupied bythe portion of curved member 254 that is not overlapped by rigid member256, is termed herein below as the “curved supported section” ofexternal sheath 258. A distal section of external sheath 258, which isoccupied solely by flexible member 252 is in a straight shape. Theoperator can further push distally only external sheath 258 which isfloppy and functions as an atraumatic tip.

The length of each section of access system 250 is determined by thelengths of each of supporters 252, 254 and 256, and by their relativeoverlap, as determined by the distance each is pushed by the operator.The curve angle of access system 250 is determined by the radius ofcurvature of curved member 254, and by the length thereof that is notoverlapping rigid member 256.

Alternatively, flexible member 252 is in the shape of an external sheathenfolding both curved member 254 and rigid member 256. In this manner,access system 250 includes only three elements, however the weakstraight external sheath has to be disposed of, disinfected orsterilized, when being used among different patients.

By enfolding access system 250 with external sheath 258, the outerdiameter of access system 250 is kept constant or at least continuous(i.e., the outer diameter does not change abruptly or forms a step). Thecontinuous outer diameter stands in contrast to telescopic systems,which diameter differs for different sections thereof. The continuousexternal diameter reduces damage to the tissues surrounding the accesssystem on the way to the sinus, and within the sinus itself. In someembodiment, the flexible member enfolds the other supporters and othercomponents of the access system, thereby functioning as an externalsheath or sleeve. In this case, the outer diameter of the enfoldingflexible member is continuous for reducing the damage to the surroundingtissues.

In accordance with another embodiment, the access system furtherincludes a locking mechanism (not shown), for locking all supporterstogether (e.g., straight flexible member, curved member and straightrigid member). In other words, the locking mechanism prevents relativemovement between the supporters. Alternatively, the locking mechanismonly locks two of the supporters together. For example, the lockingmechanism locks the rigid member to the curved member such that relativemovement is disabled (i.e., when moving one of the supporters, the othersupporter is also moved in the same way). The locking mechanism isimplemented, for example, by a wire coupled to both the distal end andthe proximal end of the access system (i.e., or the housing). In theunlocked mode, the wire is untight (i.e., flabby), while in the lockedmode the wire is stretched so that the supporters are fixed together andcannot be separately moved. Alternatively, other locking mechanisms canbe employed, such as a locking sleeve, a locking component which changesits shape or rigidity when energy (e.g., thermal or electrical energy)or when pressure is applied thereto.

The locking mechanism can be either locked, such that the supporters arebound together, or unlocked such that each supporter can be movedseparately. During insertion, or extraction, of the access system into,or out of, the paranasal sinus, the locking mechanism is unlocked. Thatis, relative movement between the supporters is enabled. Even when thelocking mechanism is locked, the operator can further push or pull thesupporters of the access system together (i.e., with substantially norelative movement between the supporters). When the distal tip of theaccess system is in the required position (e.g., at the desired locationwithin the sinus cavity), the locking mechanism is locked, and relativemovement between the supporters is disabled. Thus, for example, theaccess system is maintained in place while the operator retracts thesystem or carries out an operation (e.g., using a swab). In accordancewith another example, the locking mechanism is locked prior to insertionof the access system to the body of the patient, until the rigid memberis properly positioned in the vicinity of the paranasal sinus.Thereafter, the locking mechanism is released (i.e., unlocked), forallowing the rigid member to be retracted, or the curved member to befurther advanced. In accordance with a further embodiment, the shape ofthe external sheath can be made tapering (e.g., conical) such that thecross section of the distal end thereof is smaller than the crosssection of the proximal end thereof. Thereby, initial insertion of theaccess system is easier. Additionally, the tapering external sheathgradually dilates the anatomical path to the paranasal sinus and theparanasal sinus itself.

Alternatively, in case the access system does not include an externalsheath, the access system housing, or otherwise the external-mostcomponent of the access system, is tapering. For example, in case theflexible member enfolds both the strong and the curved member, theflexible member is tapering.

In accordance with yet another embodiment, rotary or incrementalencoders, or other sensors, are installed between the supporters of theaccess system for monitoring the relative movement between thesupporters. Thereby, the position of the distal end of the access systemis determined. Alternatively, the movements of the operating mechanism(not shown—e.g., levers and handles) the operator employs for operatingthe access system are monitored for determining the location of thedistal end of the access system. Further alternatively, motion sensors(e.g., accelerometers and gyroscopes), or position detectors (e.g.,ultrasonic or electromagnetic) are installed on, or in the vicinity of,the distal head of the access system for determining the position andorientation of the distal head of the access system.

The access system of the invention enables the operator to reach morethan one sinus cavity (e.g., maxillary and frontal) with the same accesssystem, and without retracting the system from the patient's body. Forexample, while the rigid member is maintained within the patient's nose,the operator can maneuver the access system among the different sinuscavities. Accessing two or more sinus cavities without fully retractingthe access system saves time and effort to the operator, and reduces theinconvenience to the patient.

Reference is now made to FIG. 5, which is a schematic illustration of anexternal sheath 300 of a paranasal sinus access system, according to oneembodiment. External sheath 300 includes a sheath body 302 and afunctional distal head 304 (i.e. worktool). External sheath 300 isdisposed around a sinus access system (e.g., access system 250 of FIGS.4A-4F), which is employed for accessing a paranasal sinus of a patient.After insertion into the sinus cavity, the access system can bewithdrawn from the body of the patient while external sheath 300 remainstherein, for providing access therethrough for at least one tool intothe sinus.

In the example set forth in FIG. 5, functional distal head 304 is a swabhead 305. Swab head 305 is directed at acquiring a tissue sample orother sample from within the paranasal sinus of the patient. Theoperator rubs swab head 305 against the inner tissue of the sinus foracquiring tissue sample. Alternatively, functional distal head caninclude other tools for performing other actions within the sinus of thepatient such as a dilation balloon, a camera, a heat source, a lasersource, a light source, drainage nozzle, irrigation nozzle, injectionelement, and the like.

In accordance with another embodiment, the functional distal head of thesystem is rotatable (not shown). The rotatable head can be moved (e.g.,rotated) separately from the supporters of the access system. Thereby,the rotatable functional distal head provides at least one additionaldegree of freedom to the access system. The movement of the rotatablehead can be controlled, for example, by employing wires, applyingthermal energy to shape memory materials or by other actuatingmechanisms.

Once the access system is properly positioned within the sinus of thepatient, the access system can be secured in place (e.g., by employing alocking mechanism or a balloon), such that only the functional distalhead 304 can be rotated (i.e., or otherwise moved). When the rotatablehead is also properly positioned at the desired location andorientation, it can be secured in place as well, and the operator canoperate the functional element of the rotatable function distal head.Once the access system and the rotatable head are secured in place, atleast some of the supporters can be retracted from the body of thepatient.

For example, the rotatable functional distal head can include opticalsensors and other optical components (e.g., lenses, prisms and mirrors)for enabling the operator to view (i.e., or to image) the interiorvolume of paranasal cavity. The rotatable head including the opticalsensors can be rotated to enable the operator to examine differentportions of the paranasal cavity.

In accordance with a further embodiment, the functional distal headincludes at least one port (not shown). For example, the port can beconfigured as a port for transfer of fluids (e.g., gas or liquid) intoor out of the sinus cavity (i.e., fluids port). The fluids port iscoupled with a fluid passageway through which the fluids pass. Forinstance, in case the flexible member is tubular, its lumen can serve asthe fluids passageway. Alternatively, the work channel of the accesssystem can include, or can serve as, the fluid passageway.

The fluid port can be formed as an opening in the functional distal headenabling fluids passage through the distal head. The fluid passagewaycan be formed by a single channel (i.e., conduit), or a network ofchannels. The distal end of the fluid passageway (i.e., located out ofthe body of the patient) is connected to a fluid container and possiblyto a fluid pumping mechanism (e.g., a syringe or a pump), for pumpingthe fluid through the fluid passageway into or out of the sinus cavity.The fluids can be, for example, saline, biological agents, chemicalagents, drugs, antibiotics supporter, and the like. The fluids can beemployed for irrigation, cleaning other components installed on thefunctional head (e.g., optical components such as a camera orillumination components such as a fiber bundle).

The fluid port, or the fluid passageway, can include a valve forregulating fluid passage therethrough. For example, the valve can beemployed for switching fluid passage modes, such as switching between anirrigation mode, in which fluids are irrigating the sinus cavity, andbetween camera cleaning mode, in which fluids are directed toward thecamera for cleaning it. The valve can be controlled by the fluidpressure or by another remote control mechanism, such as a pull wire,applying electrical energy to a piezoelectric element, and the like. Thefluids pumped into the sinus cavity can be employed for collectingintracavity tissue, mucous and liquids samples by flooding the sinuscavity (e.g., with saline), collecting the flooding fluid, and filteringtissue, mucous and liquids samples therefrom.

The functional head can include several ports that can either beidentical or different than each other. The ports can be formed andemployed for different applications. The different ports can be coupledwith separate fluid channels, containers and pumping mechanisms. Theports of the functional head can further include therapeutic ordiagnostic probes (e.g., a laser source, an IR source, an ultrasoundsource). The ports can also include sensors, such as position sensors,velocity sensors, acceleration sensors, temperature sensors, pressuresensors, biological sensors, chemical sensors, force sensors,electro-optical sensors, and the like. For example, each image acquiredby a camera installed on the functional head is associated with readingsfrom a magnetic position sensor mounted on the head.

In accordance with yet another embodiment, the functional distal head ofthe access system is displaceable with respect to the access system. Forexample, the distal head is coupled to sheath body 302 (or to theflexible member—not shown) via a hinge. In this manner, the functionaldistal head can switch between a first position in which it seals thedistal end of sheath body 302, and a second position in which the distalend of sheath body is open. For instance, when the operator pushes theaccess system into the body cavity, the distal head that includes acamera provides a frontal view of the passed through anatomy to theoperator. Once the operator reaches the required location within thebody cavity, the distal head is opened, thereby, enabling the operatorto transfer a working tool via the body sheath.

Furthermore, the displaceable distal head may include back-to-backarrangement. In other words, a first side of the distal head includes acamera, and the other side includes a tissue sampling tool (e.g., aswab). Thus, the operator employs the camera for accessing the sinuscavity, and once positioned there-within, the operator switches thesides of the functional head, and can employ the swab for samplingintracavity tissue, mucous and liquids. Alternatively, the back-to-backarrangement includes a first camera (and/or illumination) in a firstside of the distal head, and a second camera (and/or illumination) inthe other side. Thus, the operator employs the first camera foraccessing the sinus cavity, and once positioned therewithin, theoperator switches the sides of the functional head, and can employ thesecond camera while simultaneously employing a working tool within thesinus cavity.

In the examples set forth herein above with reference to FIG. 5, thefunctional distal head is coupled at the distal end of an externalsheath. Alternatively, the functional distal head is coupled with thedistal most element of the access system. For example, in case theflexible member enfolds the other supporters of the access system andfunctions as the external sheath, the functional distal head is coupledat the distal end of the flexible member.

Reference is now made to FIGS. 6A and 6B, which are schematicillustrations of an external sheath 330 of a paranasal sinus accesssystem, according to another embodiment. External sheath 330 includes asheath body 332, a swab head 334, and a foldable sleeve 336. Foldablesleeve 336 includes an unstitched hem 338. Foldable sleeve 336 enfoldssheath body 332 and swab head 334. In particular, foldable sleeve 336 iscoupled with sheath body 332 proximally to the distal end (notreferenced) of swab head 334, such that unstitched hem 338 enfolds swabhead 334. Each of sheath body 332 and swab head 334 is substantiallysimilar to sheath body 302 and swab head 305 of FIG. 5, respectively.

Foldable sleeve 336 is sealed and prevents sheath body 332 and swab head334 from coming into contact with the tissues of the patient duringinsertion of the access system and external sheath 330 into theparanasal sinus of the patient. Once swab head 334 is positioned withinthe sinus cavity, the operator may remove the access system from thebody of the patient. When swab head 334 is positioned within the sinuscavity, the operator of the access system pulls foldable sleeve 336proximally (i.e., in the example set forth in FIGS. 6A and 6B, theproximal direction is to the right hand side of the Figure) such thathem 338 is straightened, and swab head 334 is exposed. The operator rubsswab head 334 against the inner tissue of the sinus for acquiring tissuesample. The operator removes external sheath 330, including the tissuesample within swab head 334 for analyzing the sampled tissue. In thismanner, the operator samples only the sinus tissue (i.e., and not othertissues on the way to the sinus tissue), thereby, increasing theaccuracy of analysis of the tissue sample.

Sheath body 332 remains enfolded within sleeve 336 throughout theinsertion of access system 330 into the sinus and therefore remainssterile. Therefore, the access system enfolded within external sheath330 (i.e., in case it is not retracted by the operator) can be re-usedfor another patient, once sleeve 336 and swab head 334 are replaced(i.e., disposable elements), disinfected or sterilized. Sheath body 332can further include a work channel. Thus, sheath body 332 can house atleast one working tool, such as a camera. The camera can acquire imagesof the sinus cavity and throughout the insertion of the access system tothe sinus. In a similar manner to the access system within sheath body332, the camera is protected by sleeve 336 and is re-usable as well.Alternatively, sheath body 332 can contain other re-usable workingtools, such as an ultra-sound imager, a heat source, or a laser source,as long as the tools are not required to come into contact with thesinus tissues.

Reference is now made to FIGS. 7A and 7B, which are schematicillustrations of an external sheath 370 of a paranasal sinus accesssystem, according to yet another embodiment. External sheath 370includes a sheath body 372, a functional distal head 374, and apuncturable sleeve 376. External sheath 370 enfolds a paranasal sinusaccess system. Additionally, sheath body 372 can enfold other tools,such as a camera, or a laser source. Puncturable sleeve 376 enfoldssheath body 372 and functional distal head 374. Each of sheath body 372and functional distal head 374 is substantially similar to sheath body302 and functional distal head 304 of FIG. 5, respectively.

Puncturable sleeve 376 prevents sheath body 372 and functional distalhead 374 from coming into contact with the tissues of the patient duringinsertion of the access system into the paranasal sinus of the patient.When functional distal head 374 is positioned within the sinus cavity,the operator of the access system pulls puncturable sleeve 376proximally (i.e., in the example set forth in FIGS. 7A and 7B, theproximal direction is to the right hand side of the Figure) such thatfunctional distal head 374 punctures the distal end of puncturablesleeve 376 and is thereby exposed. Alternatively, the operator pushesfunctional distal head 374 distally to puncture puncturable sleeve 376.The operator employs functional distal head for performing an actionwithin the tissue of the patient, such as inflating a dilation balloonwithin the ostium of the sinus, acquiring tissue sample from the sinus,ablating tissues of the sinus, irrigating the sinus, draining fluidsfrom the sinus, injecting substances into the sinus (e.g., localizeddrug delivery), and the like. Sheath 372 can either be re-usable upondisinfection or sterilization, or can be disposable. The access systemsealed within the sheath body 372, as well as other working tools whichare sealed within sheath body 372 (e.g., a camera) can be re-used forother patients.

Reference is now made to FIG. 8, which is a schematic illustration of aparanasal sinus environment, generally referenced 400, which is accessedby an access system, according to another embodiment. Sinus environmentdepicts a paranasal sinus cavity 402, a sinus cavity flap 404 (e.g., theuncinate process), an access system 406 and a working tool 408. Accesssystem 406 is a paranasal sinus access system substantially similar toaccess system 250 of FIGS. 4A-4F. Access system 406 includes a workchannel, through which an operator of access system 406 can insertworking tool 408 into sinus cavity 402. Working tool 408 is a working,therapeutic or diagnostic tool for performing an action within cavitysinus 402. For example, working tool 408 can be a camera, a ballooncatheter, a washing catheter, a draining catheter, a tissue ablatingtool, a grasper, a biopsy collector, and the like.

As can be seen in FIG. 8, for accessing sinus cavity 402, access system406 (i.e., and in particular the work channel within) have to maneuveraround sinus cavity flap 404 and make a turn of an angle exceeding 90degrees. Such an acute turn in a limited space as that of the anatomy ofthe nasal cavity and the paranasal sinuses, requires that access system406 would maneuver to achieve a wide range of curve angles over a verysmall radius of curvature. In particular, for accessing sinus cavity402, access system 406 should conform to a radius of curvature ofbetween 2-5 mm, and achieve angles up to 180 or even greater thandegrees.

As mentioned above with reference to FIGS. 4A-4F, shape memory elementsregain their original shape after being deformed. However, the shaperegaining is not unlimited and an element which is drastically deformedmight not fully regain its original shape. With reference to FIGS.4A-4F, curved member 254 is positioned off the center (not shown) of thecross section of sheath 258. In particular, curved member 254 ispositioned at, or toward, the end of the cross section of sheath 258,which is furthest away from sinus cavity 404. That is, the curved memberis positioned at, or toward, the extrados of the bend of the accesssystem. Thereby, the radius of curvature of curved member 254 is largerthan in case curved member 254 would have been positioned in the centerof the cross section of sheath 258.

Additionally, curved member 254 is non-tubular, e.g., a bar shaped. Abar shaped shape memory element may withstand higher deformations than atube shape element. Furthermore, a tube shaped element when deformed bya curvature may become oblate (i.e., its cross section becomes oval)thereby decreasing its diameter in one axis. Therefore, every elementpassing through curvedly deformed tube should have a diameter smallerthan that of the tube for allowing for the oblation of the tube. Forexample, the diameter of working tool 408 should be sufficiently smallerthan that of the work channel of access system 406, for allowing for theoblation of the work channel when curvedly deformed by the curvedmember.

In accordance with another embodiment, the curved member is formed by awire made of shape memory material. The cross section of the wire can beof any shape, such as circular, oval, rectangular, hexagonal, and thelike. Alternatively, the curved member is formed by more than a singlewire. For example, the curved member is formed from two or more wirescoupled together side by side. For instance, the wires can have acircular cross section, or a rectangular cross section (i.e., therebyforming together a bar shaped curved member).

In accordance with a further embodiment, the curved member is bar shapedand the rigid member is tube shaped. The rigid member includes a distalend configured to enable coupling (e.g., slidable coupling) between thetwo supporters. The distal end of the straight rigid member may includea curved member recess configured to receive the curved member, asdepicted, for example, hereinafter in FIGS. 16A-18B. Additionally, thedistal end enables the flexible member to smoothly move (e.g., slide)over the rigid member and the curved member, and in particular, over theend of the rigid member where the curved member is being curved.

Reference is now made to FIG. 9, which is a schematic illustration of anaccess system, generally referenced 430, constructed and operative inaccordance with yet a further embodiment. Access system 430 includes anexternal sheath 432 and a working tool 434. Sheath 432 is substantiallysimilar to sheath 402 of FIG. 8, and enfolds therewithin a flexiblemember, a curved member and a rigid member (all not shown). Working tool434 slidably passes through a work channel (not shown) of sheath 432. Ascan be seen in FIG. 9, working tool 434 can be rotated around itscentral axis 438 without rotating sheath 432. In particular, workingtool 434 rotates around axis 436 and 438 without moving sheath 432.

Reference is now made to FIG. 10, which is a schematic illustration of aballoon dilation catheter, generally referenced 470, according toanother embodiment. Balloon dilation catheter 470 includes a firstballoon 472, a second balloon 474, and a fluid channel 476. Firstballoon 472 and second balloon 474 are in fluid communication with eachother. Fluid channel 476 is in fluid communication with both firstballoon 472 and second balloon 474 for providing fluid (e.g., salinesolution, air) to first and second balloons 472 and 474. Each of firstballoon 472 and second balloon 474 can either be a compliant,semi-compliant or non-compliant balloon. In the example set forth inFIG. 10, first balloon 472 is a compliant or semi-compliant balloon, andsecond balloon 474 is a noncompliant balloon.

An operator of an access system (e.g., access system 250 of FIGS. 4A-4F)employs the access system for accessing a paranasal sinus of a patient.The operator inserts balloon dilation catheter 470 through a workchannel of the access system. Alternatively, balloon catheter 470 isdetachably mounted over the access system (e.g., similarly to externalsheath 300 of FIG. 5).

Both first balloon 472 and second balloon 474 are deflated duringinsertion into the sinus cavity. The operator positions first balloon472 within the sinus cavity of the patient, and positions second balloon474 within the ostium of the sinus (i.e., the opening to the sinuscavity). The operator inflates both first balloon 472 and second balloon474, for gradually broadening the ostium (i.e., increasing the diameterthereof). Second balloon 474 is constrained by the ostium and thereforecan only inflate to a certain volume. First balloon 472, which ispositioned within the sinus cavity, is not constrained and can beinflated to its maximal volume and stretch (i.e., in case of compliantor semi-compliant balloon).

As detailed above, first balloon 472 is in fluid communication withsecond balloon 474. Therefore, the pressure between balloons 472 and 474is in equilibrium. Thus, compliant or semi-compliant first balloon 472,serves as a pressure reservoir for non-compliant second balloon 474. Assecond balloon 474 is pressed against the walls of the ostium of asinus, any change in the dimensions of the ostium is compensated by avolume change of first balloon 472 for maintaining the pressureequilibrium.

First balloon 472 and second balloon 474 are maintained within the sinuscavity and the ostium of the sinus, respectively, for a period of timedetermined by the operator (e.g., one hour, one day or one week). Theoperator can remove the access system and balloon catheter 470, whilemaintaining balloons 472 and 474 in the sinus and ostium. After thatperiod of time has ended, the operator removes both balloons from thesinus and ostium of the patient by re-employing the access system.

In accordance with an alternative embodiment, the access system (e.g.,access system 250 of FIG. 4A) is coupled with a balloon. The operator ofthe access system can inflate and deflate the balloon, for example, fordilating sections of the anatomy of the patient on the way to the sinuscavity, or within the sinus cavity itself.

Further alternatively, the access system includes a dilating tubeenfolding the access system. The dilating tube can be, for example, asleeve having a tapering distal end, that enfolds the access system andthat can be inflated and deflated by the operator for dilating sectionsof the anatomy of the patient. The dilating tube is coupled with a fluidchannel running along, outside, or within, the access system. The fluidchannel enables an inflating fluid (e.g., saline) to be pumped into orout of the dilating tube. The fluid channel is coupled with an inflatingfluid reservoir on the proximal end of the access system, outside of thebody of the patient. The dilating tube can enfold the entire length ofthe access system or only a section of the access system (e.g.,enfolding the distal end of the access system or enfolding a sectionwhich is positioned proximally to the distal end). The operator canemploy the dilating tube to dilate sections of the anatomy of thepatient within the sinus cavity or on the way to the sinus cavity.Additionally, the operator can employ the dilating tube for anchoringthe access system in place by inflating the dilating tube such that itsnuggly fits the surrounding anatomy of the patient. Thereby theinflated dilating tube prevents the access system from sliding distallyor proximally from its current location.

Reference is now made to FIG. 11, which is a schematic illustration of aballoon dilation catheter, generally referenced 500, constructed andoperative in accordance with yet a further embodiment. Balloon dilationcatheter 500 includes a balloon holding sleeve 502, a series of balloons504A, 504B, 504C, 504D, and 504E, and a balloons inflation channel 506.Each of balloons 504A-504E is in fluid communication with adjacentballoons. Balloons inflation channel 506 is in fluid communication withballoons 504A-504E.

An operator inserts balloons 504A-504E into the ostium of a paranasalsinus of a patient by employing an access system (e.g., access system250 of FIGS. 4A-4F). During insertion, balloons 504A-504E are enfoldedby balloon holding sleeve 502, and are deflated. When arriving to theostium, the operator pulls balloon holding sleeve 502 proximally toexpose at least one of balloons 504A-504E. In the example set forth inFIG. 11, the operator exposes four balloons 504B-504E, while maintaininga single balloon 504A enfolded within balloon holding sleeve 502.Thereby, the operator controls the length of the balloon employed in thedilation procedure. Balloon dilation catheter 500 can include any numberof balloon (e.g., two balloons or eight balloons).

Once balloons 504B-504E are positioned within the ostium of a sinus, theoperator can remove the access system while maintaining balloons504A-504E, balloon holding sleeve 502 and balloons inflation channel 506within the patient. It is noted, however, that the proximal end ofballoons inflation channel 506 remains outside of the body of thepatient. The operator inflates balloons 504B-504E via balloons inflationchannel 506 for applying pressure on the walls of the ostium forincreasing the diameter thereof. After a period of time, the operatorcan deflate balloons 504B-504E, and remove balloons 504A-504E, holdingsleeve 502 and balloons inflation channel 506 by employing the accesssystem.

Reference is now made to FIGS. 12A-12C, which are schematicillustrations of a system for accessing a paranasal sinus of a patientgenerally referenced 530, according to another embodiment. Access system530 includes an external sheath 532, an inner curving tube 534, and apull wire 536. External sheath 532 enfolds inner curving tube 534. Pullwire 536 runs through a dedicated wire channel (not shown) on theperimeter of curving tube 534. Pull wire includes two restrain beads 538at either end thereof. Sheath 532 is formed of a rigid material. Curvingtube 534 is formed of a flexible material which can be flexed uponappliance of pressure. Additionally, system 530 can further include astraight semirigid supporter (i.e., a flexible member—not shown),slidably coupled within curving tube 534. Further additionally, a toolcan also slide through curving tube 534 along the flexible member.

With reference to FIG. 12A, curving tube 534 is slidably coupled withinsheath 532 and is pushed distally (i.e., in the example set forth inFIGS. 12A-12C the distal direction is toward the left hand side of theFigure) by an operator of access system 530. With reference to FIG. 12B,once the operator wants to curve access system 530 around an obstacle(e.g., sinus cavity flap 404 of FIG. 8), the operator pulls wire 536while pushing curving tube 534 proximally, thereby, curving tube 534begins to curve. With reference to FIG. 12C, the operator can controlthe curve angle of curving tube 534 by continuing to push curving tubedistally, while pulling wire 536 proximally, until reaching the desiredcurve angle. It is noted, that the operator can pull wire 536, whilecurving tube is positioned within sheath 532. Thereby, sheath 532 wouldconstrain curving tube 534 from curving in a similar manner to a rigidmember.

Reference is now made to FIG. 13, which is a schematic illustration of acurved member producer, generally referenced 560, constructed andoperative with yet a further embodiment. Curved member producer 560includes a radius shaper 562 and a curved member 564. Radius shaper 562is made of a shape memory material and is curved. Alternatively radiusshaper 562 is a steerable sheath (e.g., curving sheath 534 of FIGS.12A-12C, or other deflection mechanism). Radius shaper (i.e., in case itis made of shape memory material) 562 is more rigid than a flexiblemember (not shown) and is less rigid than a rigid member, both of anaccess system (e.g., system 100 of FIGS. 1A-1D). Thus, when radiusshaper 562 extends beyond the rigid member, i.e. non-overlapping areas,radius shaper 562 regains its original curved shape. In the examples setforth in FIG. 13, three alternative radius shapers 562 are shown, havingdifferent curvatures. Curved member 564 is elongated shaped rigidmaterial exhibiting plastic behavior. An operator of the access systempushes curved member 564 through radius shaper 562, and thereby bendscurved member 564 at a radius determined by the radius of curvature ofradius shaper 562. The operator determines the angle of curve of curvedmember by controlling the length of curved member extending throughradius shaper 562.

Reference is now made to FIGS. 14A, which is a schematic illustration ofa curved member, generally referenced 600, constructed and operativewith yet another embodiment. Curved member 600 includes a shape memoryportion 602 and a flexible portion 604. Shape memory portion 602 regainsits original shape after being deformed and thereby gives curved member600 its curved shape when not overlapping with a rigid member of anaccess system. In the example set forth in FIG. 14A, flexible portion604 is in the shape of a tube, and shape memory portion 602 is in theform of a curved helical wire. Shape memory portion 602 is wound aroundflexible portion 604.

Reference is now made to FIGS. 14B, which is a schematic illustration ofa curved member, generally referenced 610, constructed and operativewith yet a further embodiment. Curved member 610 includes a shape memoryportion 612 and a flexible portion 614. In the example set forth in FIG.14B, flexible portion 614 is in the shape of a tube, and shape memoryportion 612 is in the shape of a closed shape cut pattern having acurved shape memory.

Reference is now made to FIGS. 14C, which is a schematic illustration ofa curved member, generally referenced 620, constructed and operativewith yet another embodiment. Curved member 620 includes a shape memoryportion 622 and a flexible portion 624. In the example set forth in FIG.14C, flexible portion 624 is in the shape a tube having a strip-shapedcut pattern, and shape memory portion 622 is in the form of astrip-shaped wire mesh completing the tube shape of (i.e., filling thecut pattern of) flexible portion 614.

Reference is now made to FIGS. 14D, which is a schematic illustration ofa curved member, generally referenced 630, constructed and operativewith yet a further embodiment. Curved member 630 is made of a shapememory material and is in the form of an incomplete tube.

Reference is now made to FIG. 15, which is a schematic illustration of asplit working tool, generally referenced 670, constructed and operativewith yet another embodiment. Split tool 670 is inserted into the sinusof a patient by employing an access system (e.g., system 250 of FIG.4A-4D) via lumen 676 of the access system (i.e., lumen 676 defines awork channel of the access system). Split tool includes a bifurcateddistal head tool 672 and a bifurcated proximal tool 674. Distal headtool 672 occupies the distal end of split tool 670 and is substantiallyshort (e.g., a camera, a laser source and the like). Proximal tool ispositioned proximally to distal head tool 672 (i.e., concentric withdistal head tool 672) and can either be short or elongated (e.g., anirrigation or drainage catheter). When split tool 670 extends distallyto lumen 676, split tool 670 splits such that both distal head tool 672and proximal tool 674 are parallel to each other.

Reference is now made to FIGS. 16A and 16B, which are detail schematicillustrations of distal end 702 of a rigid member, generally referenced700, constructed and operative with yet a further embodiment. FIG. 16Adepicts the distal end of rigid member 700 from an isometricperspective. FIG. 16B depicts the distal end of rigid member 700 from afront view perspective. Rigid member 700 together with a flexible memberand a curved member (both not shown) form together a sinus access system(not shown—e.g., access system 250 of FIG. 4A). Rigid member 700includes a distal end 702, a curved member recess 704 and a work channelrecess 706.

Distal end 702 (or at least its proximal side) of rigid member 700 hasthe same cross section as the rest of rigid member 700 such that rigidmember 700 forms a continuous elongated body. As can be seen, forexample, in FIGS. 16A and 16B, rigid member 700 and distal end 702thereof are tube shaped defining a lumen (not referenced) runningtherethrough.

Curved member recess 704 is an opening at the distal end of rigid memberenabling the curved member to pass therethrough. The cross section ofcurved member recess 704 snugly matches the cross section of the curvedmember. In the example set forth in FIGS. 16A and 16B, the cross sectionshape of curved member recess 704 (and of the curved member itself) isrectangular bar shaped having rounded corners.

The cross section of the curved member corresponds to that of curvedmember recess 704. In case the operator of the access system rotates anyone of rigid member 700 or the curved member, the other one is rotatedas well. That is, when a torsional force is applied to either one ofrigid member 700 and the curved member, the supporter on which thetorsional force is applied applies the same force on the other supportervia the snug coupling of the supporters. Thus, torsional deformation ofthe bar shaped curved member is prevented (or at least reduced).

As can be seen, in the example set forth in FIGS. 16A and 16B, curvedmember recess 704 is positioned off the central longitudinal axis ofrigid member 700 (i.e., non-concentric). In other words, curved memberrecess 704 is located at the periphery of the cross section of distalend 702 of rigid member 704. As mentioned above (with reference to FIGS.4B, 4E and FIG. 8), by being positioned off center, at the oppositedirection from the bending direction of the access system (i.e., at theextrados), the curved path of the curved member has a larger radius ofcurvature than that of the longitudinal axis of the access system.Thereby, the strain applied onto curved member when extending beyond thelength of rigid member 700 is reduced.

Work channel recess 706 is another opening at the distal end 702 ofrigid member 700. Work channel recess 706, together with the lumendefined within rigid member 700, are part of the work channel of theaccess system, through which access is provided into and out of thesinus cavity.

For example, the work channel can provide access to a working tool, suchas an optical sensor and an illumination fiber bundle, into the sinuscavity of the patient. The work channel can also enable fluids to bepumped into or out of the sinus cavity. The fluids go through the lumenof rigid member 700, along the curved member, and through work channelrecess 706. Thus, the internal volume of rigid member 700 is used (i.e.,for slidably passing the curved member, and for enabling a working toolor fluids, to pass therethrough), and thereby the dimensions of theaccess system can be reduced.

In this manner, fluids that pass through work channel recess 706 canthen pass through the flexible member and exit from the access systeminto the sinus cavity through a port in the distal end of the flexiblemember. Thus, fluids can be passed from a container (i.e., locatedoutside of the patient's body) into the target location at the sinuscavity (or from the target location to a container outside of thepatient's body) through the access system while the access system ismaintained in place. In other words, the operator does not have toinsert and/or retract one or more supporters, tools or any otherinstruments into (or out of) the patient's body multiple times in orderto pass the fluids.

In accordance with an alternative embodiment, rigid member 700 includestherewithin two separate channels (i.e., lumens). The first lumenenfolds the curved member of the access system, and ends at curvedmember recess 704. The second lumen defines the work channel and ends atwork channel recess 706. In this manner, the curved member is separatedfrom the working channel for preventing the working tool, or the fluids,passing through the work channel from coming into contact with thecurved member.

Reference is now made to FIGS. 17A, 17B and 17C, which are schematicillustrations of a distal end of a rigid member, generally referenced730, constructed and operative with yet another embodiment. FIG. 17Adepicts the distal end of rigid member 730 from a top view perspective.FIG. 17B depicts the distal end of rigid member 730 from a front viewperspective. FIG. 17C depicts the distal end of rigid member 730 from anisometric perspective. Rigid member 730 together with a flexible memberand a curved member (both not shown) form together a sinus access system(not shown—e.g., access system 250 of FIG. 4A). Rigid member 730includes a distal end 732, a curved member recess 734 and two workchannel recesses 736.

In a similar manner to distal end 702 of FIGS. 16A and 16B, distal end732 (or at least its proximal side) of rigid member 730 has the samecross section as the rest of rigid member 730 such that rigid member 730forms a continuous elongated body. As can be seen in FIGS. 17A-17C,rigid member 730 and distal end 732 thereof are tube shaped defining alumen (not referenced) running therethrough. Curved member recess 734 issubstantially similar to curved member recess 704 of FIGS. 16A and 16Bin terms of functionality. It is noted however, that curved memberrecess 734 is concentric with rigid member 730 (i.e., is not locatedoff-center).

In the example set forth in FIGS. 17A-17C, distal end 732 of rigidmember 730 includes two work channel recesses 736 positioned at oppositesides of distal end 732. Each of the work channel recesses 736 enablespassage of a different working tool. For example, one work channelrecess 736 enables a camera to pass through the access system, and theother work channel recess 736 enables an illumination fiber bundle topass through the access system.

Each of the work channel recesses 736 can also enable fluids to bepumped into or out of the sinus cavity. The fluids go through the lumenof rigid member 730, along the curved member, and through the workchannel recesses 736. Thus, similarly to the internal volume of rigidmember 700 depicted in FIGS. 16A-16B, the internal volume of rigidmember 730 is used (i.e., for slidably passing the curved member, andfor enabling a working tool or fluids, to pass therethrough), andthereby the dimensions of the access system can be reduced. In thismanner, fluids that pass through the work channel recesses 736 can thenpass through the flexible member and exit from the access system intothe sinus cavity through a port in the distal end of the flexiblemember. Thus, fluids can be passed from a container (i.e., locatedoutside of the patient's body) into the target location at the sinuscavity (or sucked from the target location to a container outside of thepatient's body) through the access system while the access system ismaintained in place. In other words, the operator does not have toinsert or retract one or more supporters, tools or any other instrumentsto or from the patient's body multiple times in order to pass fluidsthereto and/or therefrom.

As mentioned above, in some embodiments of the invention the flexiblemember enfolds (surrounds) the other supporters of the access system.The weak distal end of the flexible member can also be coupled with (orinclude) a functional distal head similar in structure and functionalityto those described hereinabove with reference to FIGS. 16A-B and 17A-C.Furthermore, the functional distal head described in conjunction withFIG. 5 can also be structurally and functionally similar to thefunctional distal heads of FIGS. 16A-B and 17A-C.

Reference is now made to FIGS. 18A and 18B, which are detail schematicillustrations of a distal end of a rigid member, generally referenced760, constructed and operative with yet a further embodiment. FIG. 18Adepicts the distal end of rigid member 760 from an isometricperspective. FIG. 18B depicts the distal end of rigid member 760 from afront view perspective. Rigid member 760 together with a flexible memberand a curved member (both not shown) form together a sinus access system(not shown—e.g., access system 250 of FIG. 4A). Rigid member 760includes a distal end 762, a curved member recess 764 and a plurality ofradial protrusions 766.

Radial protrusions 766 extend radially from the external surface ofrigid member 760. The flexible member (not shown) slidably enfolds rigidmember 760 and slides along radial protrusions 766. In this manner, aninner volume (i.e., intra-supporter volume) is formed between theinternal surface of the flexible member and the external surface ofrigid member 760. In other words, in case for example the flexiblemember is in form of a coil, it enfolds (i.e., and hugs) the rigidmember and the radial protrusions, thereby an intra-volume is formedbetween the flexible member and the rigid member. The size of theintra-supporter volume is determined by the height (i.e., the length ofthe radial extension of the protrusions) of the radial protrusions.

The formed intra-supporter volume can be employed as a work channel orfor enabling passage for fluids, into and out of, the sinus cavity. Inthe example, set forth in FIGS. 18A and 18B, the radial protrusion arefin shaped. Alternatively, any radial protruding element can function asthe radial protrusions 766. The radial protrusions 766 can be elongatedand run along the length of the rigid member 760, or can be short, asseen in FIG. 18A. The access system can include several sets of radialprotrusions supporting the flexible member that enfolds the rigid memberalong the length of the rigid member.

In this manner, fluids that pass through the intra-supporter volume canthen further pass through the flexible member (i.e., beyond rigid member760) and exit from the access system into the sinus cavity through aport in the distal end of the flexible member. Thus, fluids can bepassed from a container (i.e., located outside of the patient's body)into the target location at the sinus cavity (or from the targetlocation to a container outside of the patient's body) through theaccess system while the access system is maintained in place. In otherwords, the operator does not have to insert and/or retract one or moresupporters, tools or any other instruments to and/or from the patient'sbody multiple times in order to pass fluids thereto and/or therefrom.

As described herein above, according to some embodiments, the accesssystem includes three supporters that form together a tortuous path(e.g., curved path), enabling the access system to access the sinuscavity of the patient. All supporters are advanced together until afirst desired location, at which the access system should curve aroundanatomical obstacles for reaching the sinus. At the first desiredlocation, the rigid member is stopped, and the curved and flexiblemembers are advanced further. When the curved member extends beyond therigid member it regains its original curved shape, thereby producing thecurved path of the access system. The radius of curvature of the path ofthe curved member might be different than that of the flexible member.Therefore, the length of the path followed by each supporter (i.e.,curved and weak) is different for completing the same curved angle. Forexample, due to different diameters of the supporters, or because of thedifferent locations of the supporters within the access system (e.g.,the curved member is at the extrados of the bend and the flexible memberis at the intrados). This can be analogized to athletes running around acircular (or oval) ring. An athlete running at the inner lane coversless distance than an athlete running at the outer lane.

In case the operator advances the curved member and the flexible memberthe same distance together (e.g., by pushing only one of thesupporters), a compensating element can be coupled between thesupporters for coordinating their advancement along the curved path,such that both supporters complete the same curve angle together.Reference is now made to FIG. 19, which is a schematic illustration ofan access system, generally referenced 800, constructed and operativewith yet another embodiment. Access system 800 includes a rigid member802, a curved member 804, a flexible member 806, a housing 808, acompensating element 810, and a curved member coupler 812. Rigid member802, curved member 804 and flexible member 806 are slidably coupled witheach other. In a folded configuration of access system 800, housing 808houses (at least in part) supporters 802, 804 and optionally 806.Supporters 802, 804 and 806 can extend distally out of housing 808 wheninserted into the body of the patient. Compensating element 810 iscoupled between curved member 804 and flexible member 806. In theexample set forth in FIG. 19, one end of compensating element 810 iscoupled with flexible member 806, and the opposite end of compensatingelement 810 is coupled with curved member 804, via curved member coupler812.

Compensating element 810 can be for example, a coil, a biasing spring,or a stretchable wire. Alternatively, the compensating element can beformed from other components and elements for coordinating the movementof the curved member and the flexible member across the curved path(e.g., gears). Alternatively, the compensating element can beaccommodated in the housing 808. In the example set forth in FIG. 19,compensating element 810 is a spring (i.e., compensating spring 810).Compensating spring 810 enables simultaneous and coordinated movement ofboth curved member 804 and flexible member 806.

Initially, when all supporters are overlapped (i.e., in a straightposition), compensating spring 810 is loaded (i.e., preloaded). Ascurved member 804 advances distally, compensating spring 810 becomesunloaded, enabling the simultaneous and coordinated movement of the twosupporters (i.e., curved and weak). As mentioned above, when both curvedmember 804 and flexible member 806 are pushed together, each follows adifferent path and therefore, covers a different distance (i.e., for thesame curve angle). Thereby, by pushing both supporters, one wouldadvance further than the other. Compensating spring 810 compensates forthe different paths followed by the supporters and enables bothsupporters to be advanced in a coordinated fashion. In summation, thefunction of the compensating element can be analogized to the functionof a car differential that coordinates the rotations of the wheelsduring turns, thereby compensating for the different distances coveredby the wheels during turns.

When the operator completes the curving of the access system, and wishesto advance the flexible member beyond the curved member, the operatoremploys a release mechanism (not shown) for releasing compensatingspring 810 from at least one of the supporters, thereby enablingadvancement of only the flexible member. The release mechanism can beformed of components, such as wires, piezoelectric elements, and thelike.

With reference to FIGS. 20-35, various embodiments of a modular accessdevice, system and method are described below. The embodiments generallyinclude a handle and a sinus access member (which may also be called a“steerable work tool positioning member” or simply an “access member”).The described embodiments may be used for providing access to, and insome cases guiding one or more work tools to, a treatment area in ahuman or animal body. As mentioned above, the clinical example used indescribing FIGS. 20-35 will be accessing and guiding work tools to aparanasal sinus, but this is only one example and is not intending to belimiting. The system, device and method embodiments described belowgenerally include a rigid straight member, a curved shape memory memberthat is less rigid than the rigid straight member, and a flexiblestraight member that is less rigid than the curved member. At least twoof these three members are slidably coupled to the other members, sothat by advancing and retracting relative to one another they allow theaccess device to steer through tight anatomical passageways and thustreat difficult to access cavities and other treatment areas. Again, theexample used below is navigation through the nasal cavity to access theparanasal sinuses for treatment of the sinuses. The embodimentsdescribed below may use any one or more of the embodiments and/orfeatures described above for providing articulation/steering of a deviceor the like.

Referring to FIG. 20, a modular body cavity access system 970 isillustrated, connected to a camera control unit 901. In someembodiments, access system 970 may also include control unit 901 oranother embodiment of a control unit, but for the purposes ofsimplicity, access system 970 will generally be described herein as notincluding camera control unit 901. The illustrated embodiment of accesssystem 970 is for accessing human paranasal sinuses, but as mentionedpreviously, access system 970 may be used or modified for use in otherparts of the body and for other purposes. In general, access system 970includes a handle 900 at its proximal end and a steerable paranasalsinus access member 908 at its distal end. System 970 may optionally bewirelessly or physically connected to camera control unit 901 via apower and data cable 902 to a power-data port 903, which may be part ofsinus access member 908. In one embodiment, the distal end of handle 900is removably connected to sinus access member 908. In such anembodiment, handle 900 may be reusable, and sinus access member 908 maybe disposable. This two-part embodiment of access system 970 may bereferred to as “modular,” in that it includes a handle “module” and aworking end or sinus access end “module.” In alternative embodiments,handle 900 and sinus access member 908 may be permanently attached.

Referring to FIGS. 21a, 21b, 22a, and 22b , the handle 900 of the accesssystem 970 is described in more detail. In this embodiment, handle 900includes a handgrip housing 930 (or simply “a housing”), a curvingactuator 912 and a worktool extension actuator 914. The curving actuatorslides back and forth, relative to housing 930, to advance and retractthe curved shape memory member (for example, a terminal section ofnitinol 927 attached to the distal end of curving member extension rod915) and thus adjust the overlap of the curved shape memory member 927and a rigid member 920 (or “relatively stiffer straight structuralsupport,” see FIG. 23C), to allow for curving and straightening of thedistal end of the access system 970. The extension actuator 914 actsthrough B-connector 931 to advance and retract a flexible extension tube923 (or “flexible straight member” or “flexible tube”) beyond the curvedshape memory member 927 and/or beyond the rigid member 920. The rigidmember 920 is, in some embodiments, fixedly attached to the housing 930,so that it does not move. The curved member 927 and the flexible member923 slide longitudinally relative to one another and relative to therigid member 920, to provide curving and extension of the access system970, thus providing steering. In some embodiments, the curving actuator912 and the extension actuator 914 may be combined into one slidingbutton (or “sliding actuator”) or attached together. In one embodiment,the curving actuator 912 function may be actuated by pressing down onthe one sliding button and advancing or retracting it, while theextension actuator 914 function may be actuated by sliding the onesliding button without pressing down on it. An alternative embodimentmay include the opposite pressing/sliding configuration.

In this description, the curved member 927 is generally referred to withthe number label 927, although the term “curved member 927” generallyrefers to the entire part that includes the distal curved portion 927and the proximal straight portion or “rod” 915. Similarly, the term andnumber label “flexible member 923” is used to refer to the entire partthat includes the proximal portion 923 and the distal spring portion924. This terminology is used to simplify the description, so that thecurved member 927 and the flexible member 923 can be referred to as onepart apiece, rather than describing their multiple portions or parts ateach mention.

Handle 900 may also include a rotational indexing mechanism 921 forsynchronously, controllably rotating all of the slidably-coupled andextendible structural support members in unison in sinus access member908 around the longitudinal axis, either in small, controlled incrementsor continuously. Handle 900 may also include a spring-loaded sinusaccess member port 919 for detachably receiving and engaging asubstantially cylindrical and concentrically arranged D-connector 932,C-connector 934 and worktool inner connector 933 of sinus access member908, whereby the distal spring portion 924 of flexible member 923 andthe distal portion of curved member 927 that has been received in andengaged with port 919 are independently steerable and independentlyextendable beyond the curvature point by actuating curving actuator 912and extension actuator 914.

Referring to FIG. 25B, in one embodiment, the access system 970 mayinclude a power cell 956 for providing a power supply and a wirelessdata transfer for transferring data to and from a working tool 926 (FIG.26). Thus, such an embodiment of access system 970 may be wire-free. Theaccess system 970 may also include a light source 954 in the proximalportion of sinus access member 908. The light from light source 954 istransmitted to the distal end 926 of the sinus access member 908 viaoptical fibers 952 routed through a hub 909 and to a distal end of thecamera 926 through work channels provided, for example, in the rigidmember 920 or wrapped under a layer of ePTFE 905 on the outside of theflexible straight support member 923. Alternatively, a light source,wireless or Bluetooth radio transmitter and power source may all beincorporated in the handle 900. In this case, optical and electricalinterfaces would be included in control handle 900, and correspondinglyin sinus access member 908.

In some embodiments, the mechanically-steerable tool-positioningmechanism is imbued with a capacity to aim the distally placed tool,such as a camera, in a direction at an angle of at least 90 degrees,preferably greater than 120 degrees, more preferably greater than 140degrees and even possibly at least 180 degrees, to the general directionof the longitudinal axis and insertion of the worktool, in as many asthree degrees of freedom or spatial planes X-Y, Y-Z and X-Z.

Referring to FIGS. 24B-24G, 26, 27 and 28, various views illustrate thelinear arrangement of rigid member 920, curved member 927 (including itsproximal portion 915) and flexible member 923 (including its distalspring portion 924), relative to one another. In these figures, thedistal end is to the left side of the figure, and the proximal end is tothe right side. Beginning at the far distal end of sinus access member908 in FIG. 26, a camera 926 is mounted and attached to a spring portion924 which, in this tubular or cylindrical exemplary embodiment, is themost flexible portion of flexible member tube 923. In alternativeembodiments, the camera 926 may any other suitable work tool, and it isshown here as a camera 926 for illustrative purposes only. Straightenertube 920, over which flexible member tube 923 can slide when actuated,comprises the distal-most portion of rigid, (least flexible, strong)support member 20. Extending into and substantially through straightenertube 920, there can be seen curving member extension rod 915, at least adistal-most portion of which is made of a curving shape memory material.At its proximal coupling end, when the sinus access member 908 iscoupled with the handle 900, curved member extension rod 915 is receivedand centered into a distal receptacle in the inner rod 939.

Referring now to FIGS. 24A-24G and 26-28, what in earlier exemplaryembodiments were shown as at least two slidably-coupled elongate supportmembers, are now each attached at their proximal ends to a series ofinterconnected slidable couplers, at least partially cylindricalconcentrically arranged tubes, locking and unlocking mechanisms andsliding actuators. Sinus access member 908 has at its proximal end alargely concentric arrangement of rods, tubes and semi-cylindricalconnectors, including C-connector 934, worktool inner connector 933 andD-connector 932, which cooperate as and with B-connector 931,A-connector 929, inner rod 939, centering rod 917, connector engagers,extensor-retractor elements and alignment and stabilizing elements, forensuring a properly aligned fit with port 919 of handle 900, and forpermitting the necessary stable and smooth translation of a user's inputon actuators 912 and 914 into the extension or retraction of a tool suchas camera 926 located at its distal end.

Referring to FIGS. 24A-28, the curving actuator 912, which slides backand forth on sliding rod 911 when released, is connected via A-connector929 (FIGS. 24D and 27) to worktool inner connector 933, with which it iscoupled. Worktool inner connector 933 is connected at its distal end tocurved member extension rod 915, which has connected at its distal end ashape-memory nitinol portion 927.

Extension actuator 914, which initially is advanced simultaneously withcurving actuator 912, also slides along sliding rod 911 and is riding onand attached to differential compensation spring 910 (FIGS. 24D-G).Differential compensation spring 910 compensates for slackness caused bynonlinearity in travel of the most distal end of flexible member 924,and camera 926 at its end, as compared with the distal curving nitinolportion 927 at tear-drop ball-end 925 or offset bead 942. Too muchslackness or space between ball-end 925 or offset bead 942 and camera926 can lead to undesirable, uncontrolled motion, potentialcomplications thereof including inability to retract the camera 926 orunintentional puncture by advancing worktool in a slack environment. Onthe other hand, if the camera 926 is not permitted a small amount offree motion, then it might force through and damage tissue rather thanyield. Differential compensation spring 910 works to continuouslymaintain a balance between desired tension and flexibility, either inadvancing or retracting a worktool, between the distal terminal ends 926and 925, 927 or 942. Differential compensation spring 910 is connectedto cylindrical coupler B-connector 931 which is interlocked andpushes/pulls cylindrical coupler C-connector 934 in the sinus accessmember. C-connector 934 is connected at its distal end to hub 909 whichin turn is connected to most flexible least rigid extension tube 923which is connected at its distal end to coil spring 924 which has camera926 attached at its most distal end.

Anchoring the sliding members, from proximal to distal, are the slidingrod 911, joined by a frame (not shown) between frame blocks 906 (FIG.21B) to cylindrical E-connector 935 which is coupled to cylindricalD-connector 932 in sinus access member 908. D-connector 932 is connectedat its distal end to straightener tube 920. At the center of thearrangement, seen best in FIGS. 24B-24F and 26, and 27, is the curvingmember extension rod 915 and at its distal terminus the shape-memorycurving support member 904 which is both flexible yet semi-rigid, midwayin flexibility and rigidity between most rigid structural support member922 and least rigid extension tube 923.

The present exemplary embodiments illustrated in FIGS. 20-35 alsoinclude features for easily and accurately directing wires, fibers andfluids of various kinds through the access system 970 into the distalend of the worktool itself, or into cavities, sinuses and other areasthat are being accessed. Luer 916 provides a connecting structure towhich known medication delivery systems may be attached, and fluids maybe directed through channel input 907, which leads into hub 909, wherethe lumen of flexible tube 923 is open to receive the fluid and transmitit to the distal terminus. Hub 909 is a moving chamber, and as its nameimplies, it is a hub of activity and access for fluids and control wiresand fibers. At its proximal end, hub 909 is connected to C-connector934, hence the linkage to extension actuator 914. At its distal end, hub909 receives the proximal end of flexible member 923.

Referring now to FIGS. 29-31F and 33A-34D, the distal end of sinusaccess member 908 shows the nitinol portion 927 extending beyond and outof the straight, rigid tube 920. A bead 942 (or “ball tip” or “roundeddistal tip”) is sized and angled away from the overall curve of theprogrammed shape memory curving. The bead 942 is designed to spread anypressure applied against the inner walls of spring 924 and reduce therisk of puncturing or getting stuck on or in between coils, even wherecurvature spreads the coils slightly. Additionally, a dog-leg 944 (or“curve”) is outwardly angled, opposite the general inward curve of themain nitinol portion 927, directly adjacent to the offset bead 942. Inthis way, as the nitinol portion 927 emerges beyond the overlap at theslash cut end 946, and starts to curve, it does so while alwaysmaintaining a shallow attack angle and presenting a broad contactsurface against any part of the inner wall of the spring portion 924with which it makes contact. In this way, the outward force of thenitinol portion 927 is no longer perpendicular to inside wall of springportion 924, more nearly parallel thereto, and more widely distributedagainst and easily deflected by the inner wall of the spring portion924, thus reducing the chance of puncture on extension and/or snaggingon retraction.

Referring to FIGS. 30A-30G, the illustrations show curved nitinolportion 927 being retracted back into straightener tube 920. Thisfurther makes clear how the dog-leg 944, combined with the angle of bead942, tends to counter the major curvature of nitinol portion 927.

Referring now to FIGS. 31A-31F, spring portion 924 shows the interactionof the general curvature of nitinol portion 927 and counter curvingnitinol terminus dog-leg 944 and bead 942 components. Another featurealso demonstrated by the exemplary embodiment, and particularly withreference to FIGS. 30 and 31A-31F, is the use of the offsetteardrop-ball end design of bead 942, which is oriented to be biasedoutwardly, away from the general direction of curvature of curvednitinol 927, to prevent bead 942 from snagging against, or beinginserted in between, the coils of spring 924 inner wall surfaces.Finally, most clearly seen in FIG. 34A, the direction at which centeredand ball-shaped bead 960 projects from the nitinol terminus 964 is suchthat when fully retracted it is largely seated into the V-shaped recessformed by slash-cut 946 at the distal open end of rigid support member920; the partially exposed top portion of the bead 960 being effectiveto prevent any interstices between the coils of spring 924 from snaggingon the distal most extreme tip of rigid straight supporter as theworktool is retracted back into the starting fully retracted position.

Referring to FIGS. 30A-30F and 32A-32C, it was noted earlier herein thatproviding the nitinol shape-memory portion 927 with a non-roundedcross-sectional profile permits adaptations for ease of control toprevent unwanted rotation, twisting or torqueing of the shape-memorysupport member. A further structural configuration to further reduce anypossibility of longitudinal rolling of the nitinol shape memory portion927 comprises providing it with a non-rounded profile and providingrigid straightener tube 920 with at least one narrowing, stricture orcrimp 948 immediately adjacent to slash cut end 946. Examples ofnon-round cross-sectional profile shapes for ensuring the correctorientation of the nitinol shape memory portion 927 include: ellipses,polygons, semi-cylindrical, oblong and many others. FIG. 33A furtherillustrates an embodiment wherein the sinus access member is insertedinto an outer flexible sheath 954, optionally having an open orperforated distal end (not shown) which can remain in place after sinusaccess member 908 is retracted and withdrawn from a body cavity. Sheath954 can remain in place and function like a catheter, a drain, anirrigation tube for flushing or draining or introducing contrast mediafor imaging, or to reintroduce a different sinus access member into thesame location for further procedures.

Referring now to FIGS. 32A-32C, one embodiment includes an ePTFE film905 wrapped about spring portion 924 and flexible member 923. In oneembodiment, the orientation of the wrap of the ePTFE film 905 may beperpendicular to the longitudinal axis of tube 923, providing a smoothsurface to the stainless steel chassis, as well as desirable structuralreinforcement and fluid containment, to help prevent accidental punctureof tube 923 or snagging of the nitinol shape memory member indeformations, collapse, non-longitudinal expansion or separation of thecoils of spring 924.

With reference to FIGS. 32A-32C, windings of ePTFE film 905 may beapplied in several thickness patterns, for example with a conicalprofile, or capsular or any other desired contour, and that adds anydesired thickness, for example from 0 mm to 2 mm of radius, or totalcross-sectional diameter increasing from an unwrapped 2 mm to a wrapped6 mm or more. Wires 928 and/or optic fibers can be routed to a camera926, such as a camera, by being run along the outside inner curvature(or “intrados”) of flexible support members 923 and 924, and the wires928 may be held in place under the ePTFE 905 windings. Alternatively,bundles or sheath protected optic fibers can be routed outside or insiderigid straight support member 920 alongside nitinol extension rod 915.Another preferable exemplary embodiment provides a work channel formedin nitinol extension rod 915 or in the outer surface of support member920 through which fibers and fluids may be routed.

With reference to FIG. 35, an alternative embodiment of a handle 900 mayinclude T-shaped knuckle-guard-like finger grip 950 extending outwardlyfrom the housing on the side opposite the actuators 912 and 914. Inpractice, a user may grasp the handgrip housing 930, palm down, suchthat the thumb is in position to slide the actuators 912 and 914, andwith the stalk 952 of finger grip 950 between two fingers and theunderside of the T-top crossbar 954 against or adjacent the back of thefingers. Thus, the handle 900 can be permitted to “hang” from thefingers while manipulated one-handed by the user. Alternatively, a usercan hold the handle in a pencil-like grip.

The embodiments described herein provide a paranasal sinus access systemhaving a reusable handle proximally and a disposable sinus access memberdistally. According to the teachings herein, a significant portion(e.g., the entire sinus access member) of the access system can now bemade economically as a disposable piece. The teachings herein haverendered the sinus access member to be a disposable alternative, to bedisposed of after each use, and yet just as, if not more so, utilitarianand reliable as was previously known.

In accordance with another embodiment, the access system (i.e.,including the rigid, curved and flexible members) may be accommodatedwithin a housing (not shown) so that its components would be concealedfrom the patient. The housing includes a distal port through which theaccess system exits the housing and can be inserted into the body of thepatient. The operator places the housing such that the distal portthereof is located adjacent to the nostril of the patient, and theaccess system can be pushed via the nostril into the sinus cavity of thepatient. When the procedure is done, the operator retracts the accesssystem into the concealing housing, and only then the operator removesthe housing from the patient. In this manner, an awake patient can onlysee the concealing housing, thus potentially reducing patient anxiety.

In accordance with a further embodiment, and as mentioned above, acamera is coupled with the access system. The camera can be coupled atthe distal end of the access system (e.g., coupled to the functionaldistal head of the access system—e.g., functional head 304 of FIG. 5).In this manner, the operator can view the route ahead of the accesssystem during the procedure. The camera dimensions can be, for example,about 1.5 (length)×1×1 mm. Alternatively, the camera can be coupledproximally (e.g., a few millimeters) of the distal end of the accesssystem. The access system can include more than a single camera forcovering a wider field of view (e.g., imaging opposite directions), orfor stereoscopic imaging. The camera is coupled to a plurality of wires(e.g., electrical wires) configured to transfer signals from the camerato other electrical components, located proximally to the camera andpossibly outside of the patient (e.g., a processor and a sampler).

The access system can further include illumination means (i.e.,illumination devices) for illuminating the surrounding of the accesssystem for the camera. The illumination devices can be, for example,optical fibers coupled to an external light source. The flexibility ofthe optical fiber enables it to conform to the bent path of the accesssystem. According to some embodiments, the illuminating devices canfurther include lenses, prisms, reflectors, deflectors, opticalcouplers, and other optical components that can transmit light from anexternal light source through the access system.

For example, the access system can include a distal camera and two fiberbundles position on either side. The camera wiring and the illuminationbundles are passing via the work channel of the access system (i.e., orvia separate work channels). The optical fibers can be made of plastic(e.g., PMMA). The diameter of the optical fibers may be in the range ofabout 150 μm-500 μm, and preferably of about 250 μm.

The optical fibers and the camera wires are arranged so that they arenot harmed (e.g., stretched, torn, broken) during the insertion andflexion of the access system. The optical fibers and the camera wiresare preferably located at the side of the access system that is close tothe bend in the access system for shortening their path, and avoidingunnecessary stretch. That is, the optical fibers and the camera wiresare passed along the shortest peripheral curvature (i.e., internalcurvature) of the access system. Coupling the camera wires along thisinternal curvature may provide further mechanical strengthening to thesupporters' structure. For example, the un-stretchable camera wireslimit the bending of the access system. In other words, the opticalfibers and the camera wires are preferably positioned at, or toward, theintrados of the bend of the access system.

Alternatively, the optical fibers can be positioned toward the extradosof the curved path of the access system. In this manner, the radius ofcurvature of the optical fibers is enlarged for the same curved path ofthe access system. Thereby, the amount of light that escapes the opticalfibers at the curve is decreased. In other words, the flexion of theoptical fibers is reduced for reducing the amount of escaping light. Forallowing the optical fibers to be positioned toward the extrados,without stretching the fibers, the fibers may be loose when the curvedmember is overlapped with the rigid member and is straightened thereby.

In accordance with yet another embodiment, the camera (i.e., or camerasor other optical sensors) can be coupled to one or more image processorsfor handling the acquired image signals. For example, the imageprocessor can compensate for the maneuvers of the access system (i.e.,and therefore of the camera) by rotating the image, inverting the image,transposing the image, and the like. For instance, when the operatorpushes the curved member beyond the rigid member such that the accesssystem bends at an angle of 120 degrees, and the camera is thereforepartially inverted, the image processor can perform image inversion forcompensating for the camera inversion.

According to some embodiments, the handling of the acquired imagesignals may be carried out automatically or semi-automatically (i.e.,the operator is partially involved in operation), for example, based onadditional signals generated by one or more sensors (e.g., anaccelerometer or a position sensor located in the access system).Alternatively, the image handling may be controllable by the operator(i.e., manual handling). The handling of the image may further includecontrolling the illumination devices (e.g., controlling the amount oflight). Controlling any of the camera, image signals and illuminationmay be carried out (at least partially) via a user interface (e.g.,button, switch, knob, touch-sensitive screen) located in a housing(e.g., handle) of the access system.

In accordance with yet a further embodiment, additional devices can beexternally coupled to the access system and thereby be guided toward, orinto, the sinus cavity (i.e., add-on devices). The add-on devices can becoupled, for example, distally to (or at the vicinity of) the distalhead of the access system. The add-on device can be coupled, forexample, by employing a grip. The add-on devices can be, for example, aswab for collecting tissues, a needle for injecting a fluid (e.g.,therapeutic fluid or a drug), a pincer-like head for inserting orremoving pads or bandages into the patient's body, and the like. Theadd-on devices can be employed for performing actions on the way to thesinus cavity, such as local anesthetic injection, or placement orremoval of bandages.

In the examples set forth herein above, various access systems werepresented. The access systems are directed at accessing the nasal cavityand paranasal sinuses of a patient. Additionally, the access systems canbe employed for inserting a working tool via the access system.

In the exemplary embodiments, steering, or aiming, is accomplished byusing the general method described earlier of overlapping members havingdifferent rigidities and with at least one member having a shaped memorythat permits controlled formation of a desired angle, or shape. In theexemplary embodiments, determination of where the angle will form islargely dependent on where the shaped memory curving support memberextends beyond the more rigid support member to which it is slidablycoupled. Where the curving portion of the shaped-memory curving supportmember no longer overlaps the more rigid support member, it starts toresume its memorized curved shape. Once the desired angle has beenattained, and optionally a lock has been engaged to maintain thatposition, the flexible member can be slidably extended beyond the distalcurved portion to bring the worktool into the desired position.

One or more structural modifications may be made to some of theembodiments described here, to enhance safety, ease of use and/orutility and/or to reduce cost of manufacture and operation of the accesssystem. For example, in one embodiment, the end of the shape-memorycurving support member may be given an off-set teardrop or centered ballshape, which may enhance the extension/retraction of the shape-memorycurving support member as well as the least rigid straight supportmember which carries the worktool at its distal end, that will preventthe end of the shape memory curving support from locking up against, orpoking through protective coverings, if any, of the least rigid straightsupport member as they move against one another, whether in extension orretraction. Some embodiments may include external wrapping of orientedePTFE film (commonly referred to as “plumber's tape”) about theoutermost support member, which may serve to reinforce thecross-sectional integrity of that portion of the least rigid straightsupport member which must slide over and past the extended angledsection of the shape-memory curving member, without compromising therequired flexibility. In some embodiments, sufficient wrappings of ePTFEmay be used to change the effective cross-sectional diameter, therebyimparting, for example, a conical, frustoconical or capsular outer shapewhich can dilate the passages it is pushed through while notcompromising flexibility. Some embodiments may include shaping thedistal end of the tubular rigid support member with a slash cut tonestingly receive the teardrop- or ball-shaped distal end of curvingsupport member such that it is only minimally and glancingly contactedin any substantial manner by any part of flexible member, thereby alsopreventing it from being retracted too far back into the rigid straightsupport member and its partial nesting of the ball-end decreasing anypossibility of the rigid support member from snagging coils of aspring-shaped section of most the flexible support member. Having aslant cut at the end of the rigid straight support also provides for asmooth, no-step, transition when the spring portion of the flexiblemember is retracted back over the still-extended curving support memberand rigid support member; when the curving support member is extended,its inner curvature is pulled into tight contact with the tip of theslant cut and the spring cannot get stuck there; however, whenretracting the spring, it tends to move closer to the outer curvature ofthe curved nitinol (see FIG. 29) and would get stuck as it transits fromthe outer radius of the curved nitinol section 927 to the distal end ofthe most rigid support member 946, had it been left rectangular and notbeen slanted (i.e. had it been a step). Providing the handle 900 with anouter ergonomic shape and arrangement of controls may facilitatesingle-handed operation by a skilled operator.

In the above description, the access system was employed for accessingthe nasal and sinus cavities of a patient. As mentioned previously,alternative embodiments may be employed for accessing other cavitieswithin the body of a patient, or other cavities in other environments,which can only be accessed via a curved tortuous path. For example,other areas of the ear, nose and throat, abdominal cavities, thoraciccavities, reproductive system, urinary system, gastric system, braintissue, and the like.

It will be appreciated by persons skilled in the art that the inventionis not limited to what has been particularly shown and describedhereinabove. Rather the scope of the invention is defined only by theclaims, which follow.

1. A device for accessing a paranasal sinus cavity of a patient, thedevice comprising: a sinus access member, comprising: a rigid supporttube; a curved shape memory member slidably disposed at least partiallywithin the rigid support tube, wherein the curved shape memory memberassumes a default curved shape when advanced out of a distal end of therigid support tube; and a flexible tube slidably disposed over at leastpart of the curved shape memory member, wherein the flexible tubeassumes the default curved shape of the curved shape memory member whenthe flexible tube resides over the curved shape memory member; and ahandle, comprising: a housing attached to a proximal end of the rigidsupport tube; a curving slider coupled with the housing and a proximalend of the curved shape memory member for extending and retracting thecurved shape memory member through the distal end of the rigid supporttube; and an extension slider coupled with the housing and a proximalend of the flexible tube for extending and retracting the flexible tuberelative to the curved shape memory member and the rigid support tube.2. The device of claim 1, wherein the handle further comprises a springclutch coupled with the curving slider and the extension slider.
 3. Thedevice of claim 1, wherein the sinus access member further comprises anelectronics port for providing at least one of power or data transfer tothe handle.
 4. The device of claim 1, wherein the handle furthercomprises a grip member extending from an outer surface of the housingto facilitate holding the handle.
 5. The device of claim 1, wherein thesinus access member further comprises at least one additional featureselected from the group consisting of a battery housing, a wireless datatransmitter, a fluid delivery port and a light source.
 6. The device ofclaim 1, wherein the rigid support tube is attached to the housing suchthat the sinus access member can rotate relative to the handle about alongitudinal axis drawn through the sinus access member and the handle.7. The device of claim 1, wherein the handle further comprises arotational indexing port for detachably receiving and engaging a workingtool, whereby the working tool is steerable and extendable by actuatingthe curving slider and the extension slider when the working tool isreceived in and engaged with the indexing port.
 8. The device of claim1, wherein the curving slider and the extension slider are combined intoone sliding button, wherein the sliding button is configured to advanceand retract the curved shape memory member when it is depressed and isconfigured to advance and retract the flexible tube when it is notdepressed.
 9. The device of claim 1, wherein the sinus access memberfurther comprises a working tool channel configured for passage of aworking tool therethrough.
 10. The device of claim 9, wherein theworking tool is selected from the group consisting of cameras, opticalfibers, textile threads, metal threads, light sources, swabs, tweezers,sample collection containers, sample collection devices, suction tubes,irrigation tubes, injection tubes, balloons, dilation tools, ultrasoundprobes, ultrasound waveguides, infrared imaging devices, probes,sensors, stylets, and guide wires.
 11. The device of claim 10, furthercomprising the working tool.
 12. The device of claim 9, wherein theworking tool channel comprises a lumen in the flexible tube.
 13. Thedevice of claim 1, wherein a radius of curvature of the curved shapememory member in the default curved shape is between 2 millimeters and 5millimeters.
 14. The device of claim 1, wherein the flexible tubecomprises a shape memory material.
 15. The device of claim 1, whereinthe flexible tube is disposed over at least part of the rigid supporttube.
 16. The device of claim 1, wherein the flexible tube comprises aspring wrapped in polytetrafluoroethylene (PTFE) perpendicularly to alongitudinal axis of the flexible tube.
 17. The device of claim 1,further comprising a distal head coupled with a distal end of theflexible tube, wherein the distal head comprises a working tool.
 18. Thedevice of claim 17, wherein the working tool of the distal headcomprises a camera, wherein the device further comprises wires coupledwith the camera for transferring image signals, and wherein the wiresare positioned along an inner curvature of the flexible tube when theflexible tube is curved by the curved shape memory member.
 19. Thedevice of claim 18, further comprising illuminating fibers coupled withthe distal head and positioned along the inner curvature of the flexibletube.
 20. The device of claim 1, wherein the curved shape memory membercomprises: a rounded distal tip; and a curve immediately proximal to therounded distal tip.
 21. The device of claim 20, wherein the roundeddistal tip has a shape selected from the group consisting of a bead anda ball.
 22. The device of claim 20, wherein the rigid support tubecomprises a slanted distal tip, and wherein a tallest point of theslanted distal tip faces into an inner curvature of the curved shapememory member.
 23. The device of claim 1, further comprising a controlunit removably coupled with at least one of the handle or the sinusaccess member for providing at least one of power or data signals to thedevice. 24.-49. (canceled)
 50. The device of claim 1, further comprisingat least one sensor coupled with the sinus access member for allowing auser to monitor at least one of a location of the sinus access member inthe patient or relative movement between the rigid support tube, thecurved shape memory member and the flexible tube.
 51. The device ofclaim 50, wherein the at least one sensor is selected from the groupconsisting of rotary encoders, incremental encoders, accelerometers,gyroscopes ultrasonic position detectors and electromagnetic positiondetectors.
 52. The device of claim 50, further comprising at least oneadditional sensor coupled with the handle.
 53. The device of claim 50,wherein the at least one sensor is attached to the sinus access memberin a location selected from the group consisting of the rigid supporttube, the curved shape memory member, the flexible tube, a distal headof the sinus access member, between the rigid support tube and thecurved shape memory member, and between the flexible tube and the curvedshape memory member.